Как создать excel таблицу python

Installation¶

Install openpyxl using pip. It is advisable to do this in a Python virtualenv
without system packages:

Note

There is support for the popular lxml library which will be used if it
is installed. This is particular useful when creating large files.

Warning

To be able to include images (jpeg, png, bmp,…) into an openpyxl file,
you will also need the “pillow” library that can be installed with:

or browse https://pypi.python.org/pypi/Pillow/, pick the latest version
and head to the bottom of the page for Windows binaries.

Working with a checkout¶

Sometimes you might want to work with the checkout of a particular version.
This may be the case if bugs have been fixed but a release has not yet been
made.

$ pip install -e hg+https://foss.heptapod.net/openpyxl/openpyxl/@3.1#egg=openpyxl

Create a workbook¶

There is no need to create a file on the filesystem to get started with openpyxl.
Just import the Workbook class and start work:

>>> from openpyxl import Workbook
>>> wb = Workbook()

A workbook is always created with at least one worksheet. You can get it by
using the Workbook.active property:

Note

This is set to 0 by default. Unless you modify its value, you will always
get the first worksheet by using this method.

You can create new worksheets using the Workbook.create_sheet() method:

>>> ws1 = wb.create_sheet("Mysheet") # insert at the end (default)
# or
>>> ws2 = wb.create_sheet("Mysheet", 0) # insert at first position
# or
>>> ws3 = wb.create_sheet("Mysheet", -1) # insert at the penultimate position

Sheets are given a name automatically when they are created.
They are numbered in sequence (Sheet, Sheet1, Sheet2, …).
You can change this name at any time with the Worksheet.title property:

Once you gave a worksheet a name, you can get it as a key of the workbook:

>>> ws3 = wb["New Title"]

You can review the names of all worksheets of the workbook with the
Workbook.sheetname attribute

>>> print(wb.sheetnames)
['Sheet2', 'New Title', 'Sheet1']

You can loop through worksheets

>>> for sheet in wb:
...     print(sheet.title)

You can create copies of worksheets within a single workbook:

Workbook.copy_worksheet() method:

>>> source = wb.active
>>> target = wb.copy_worksheet(source)

Note

Only cells (including values, styles, hyperlinks and comments) and
certain worksheet attributes (including dimensions, format and
properties) are copied. All other workbook / worksheet attributes
are not copied — e.g. Images, Charts.

You also cannot copy worksheets between workbooks. You cannot copy
a worksheet if the workbook is open in read-only or write-only
mode.

Playing with data¶

Accessing one cell¶

Now we know how to get a worksheet, we can start modifying cells content.
Cells can be accessed directly as keys of the worksheet:

This will return the cell at A4, or create one if it does not exist yet.
Values can be directly assigned:

There is also the Worksheet.cell() method.

This provides access to cells using row and column notation:

>>> d = ws.cell(row=4, column=2, value=10)

Note

When a worksheet is created in memory, it contains no cells. They are
created when first accessed.

Warning

Because of this feature, scrolling through cells instead of accessing them
directly will create them all in memory, even if you don’t assign them a value.

Something like

>>> for x in range(1,101):
...        for y in range(1,101):
...            ws.cell(row=x, column=y)

will create 100×100 cells in memory, for nothing.

Accessing many cells¶

Ranges of cells can be accessed using slicing:

>>> cell_range = ws['A1':'C2']

Ranges of rows or columns can be obtained similarly:

>>> colC = ws['C']
>>> col_range = ws['C:D']
>>> row10 = ws[10]
>>> row_range = ws[5:10]

You can also use the Worksheet.iter_rows() method:

>>> for row in ws.iter_rows(min_row=1, max_col=3, max_row=2):
...    for cell in row:
...        print(cell)
<Cell Sheet1.A1>
<Cell Sheet1.B1>
<Cell Sheet1.C1>
<Cell Sheet1.A2>
<Cell Sheet1.B2>
<Cell Sheet1.C2>

Likewise the Worksheet.iter_cols() method will return columns:

>>> for col in ws.iter_cols(min_row=1, max_col=3, max_row=2):
...     for cell in col:
...         print(cell)
<Cell Sheet1.A1>
<Cell Sheet1.A2>
<Cell Sheet1.B1>
<Cell Sheet1.B2>
<Cell Sheet1.C1>
<Cell Sheet1.C2>

Note

For performance reasons the Worksheet.iter_cols() method is not available in read-only mode.

If you need to iterate through all the rows or columns of a file, you can instead use the
Worksheet.rows property:

>>> ws = wb.active
>>> ws['C9'] = 'hello world'
>>> tuple(ws.rows)
((<Cell Sheet.A1>, <Cell Sheet.B1>, <Cell Sheet.C1>),
(<Cell Sheet.A2>, <Cell Sheet.B2>, <Cell Sheet.C2>),
(<Cell Sheet.A3>, <Cell Sheet.B3>, <Cell Sheet.C3>),
(<Cell Sheet.A4>, <Cell Sheet.B4>, <Cell Sheet.C4>),
(<Cell Sheet.A5>, <Cell Sheet.B5>, <Cell Sheet.C5>),
(<Cell Sheet.A6>, <Cell Sheet.B6>, <Cell Sheet.C6>),
(<Cell Sheet.A7>, <Cell Sheet.B7>, <Cell Sheet.C7>),
(<Cell Sheet.A8>, <Cell Sheet.B8>, <Cell Sheet.C8>),
(<Cell Sheet.A9>, <Cell Sheet.B9>, <Cell Sheet.C9>))

or the Worksheet.columns property:

>>> tuple(ws.columns)
((<Cell Sheet.A1>,
<Cell Sheet.A2>,
<Cell Sheet.A3>,
<Cell Sheet.A4>,
<Cell Sheet.A5>,
<Cell Sheet.A6>,
...
<Cell Sheet.B7>,
<Cell Sheet.B8>,
<Cell Sheet.B9>),
(<Cell Sheet.C1>,
<Cell Sheet.C2>,
<Cell Sheet.C3>,
<Cell Sheet.C4>,
<Cell Sheet.C5>,
<Cell Sheet.C6>,
<Cell Sheet.C7>,
<Cell Sheet.C8>,
<Cell Sheet.C9>))

Note

For performance reasons the Worksheet.columns property is not available in read-only mode.

Values only¶

If you just want the values from a worksheet you can use the Worksheet.values property.
This iterates over all the rows in a worksheet but returns just the cell values:

for row in ws.values:
   for value in row:
     print(value)

Both Worksheet.iter_rows() and Worksheet.iter_cols() can
take the values_only parameter to return just the cell’s value:

>>> for row in ws.iter_rows(min_row=1, max_col=3, max_row=2, values_only=True):
...   print(row)

(None, None, None)
(None, None, None)

Data storage¶

Once we have a Cell, we can assign it a value:

>>> c.value = 'hello, world'
>>> print(c.value)
'hello, world'

>>> d.value = 3.14
>>> print(d.value)
3.14

Saving to a file¶

The simplest and safest way to save a workbook is by using the
Workbook.save() method of the Workbook object:

>>> wb = Workbook()
>>> wb.save('balances.xlsx')

Warning

This operation will overwrite existing files without warning.

Note

The filename extension is not forced to be xlsx or xlsm, although you might have
some trouble opening it directly with another application if you don’t
use an official extension.

As OOXML files are basically ZIP files, you can also open it with your
favourite ZIP archive manager.

If required, you can specify the attribute wb.template=True, to save a workbook
as a template:

>>> wb = load_workbook('document.xlsx')
>>> wb.template = True
>>> wb.save('document_template.xltx')

Saving as a stream¶

If you want to save the file to a stream, e.g. when using a web application
such as Pyramid, Flask or Django then you can simply provide a
NamedTemporaryFile():

>>> from tempfile import NamedTemporaryFile
>>> from openpyxl import Workbook
>>> wb = Workbook()
>>> with NamedTemporaryFile() as tmp:
        wb.save(tmp.name)
        tmp.seek(0)
        stream = tmp.read()

Warning

You should monitor the data attributes and document extensions
for saving documents in the document templates and vice versa,
otherwise the result table engine can not open the document.

Note

The following will fail:

>>> wb = load_workbook('document.xlsx')
>>> # Need to save with the extension *.xlsx
>>> wb.save('new_document.xlsm')
>>> # MS Excel can't open the document
>>>
>>> # or
>>>
>>> # Need specify attribute keep_vba=True
>>> wb = load_workbook('document.xlsm')
>>> wb.save('new_document.xlsm')
>>> # MS Excel will not open the document
>>>
>>> # or
>>>
>>> wb = load_workbook('document.xltm', keep_vba=True)
>>> # If we need a template document, then we must specify extension as *.xltm.
>>> wb.save('new_document.xlsm')
>>> # MS Excel will not open the document

Loading from a file¶

You can use the openpyxl.load_workbook() to open an existing workbook:

>>> from openpyxl import load_workbook
>>> wb = load_workbook(filename = 'empty_book.xlsx')
>>> sheet_ranges = wb['range names']
>>> print(sheet_ranges['D18'].value)
3

Note

There are several flags that can be used in load_workbook.

  • data_only controls whether cells with formulae have either the

formula (default) or the value stored the last time Excel read the sheet.

  • keep_vba controls whether any Visual Basic elements are preserved or

not (default). If they are preserved they are still not editable.

  • read-only opens workbooks in a read-only mode. This uses much less

memory and is faster but not all features are available (charts, images,
etc.)

  • rich_text controls whether any rich-text formatting in cells is

preserved. The default is False.

  • keep_links controls whether data cached from external workbooks is

preserved.

Warning

openpyxl does currently not read all possible items in an Excel file so
shapes will be lost from existing files if they are opened and saved with
the same name.

Errors loading workbooks¶

Sometimes openpyxl will fail to open a workbook. This is usually because there is something wrong with the file.
If this is the case then openpyxl will try and provide some more information. Openpyxl follows the OOXML specification closely and will reject files that do not because they are invalid. When this happens you can use the exception from openpyxl to inform the developers of whichever application or library produced the file. As the OOXML specification is publicly available it is important that developers follow it.

You can find the spec by searching for ECMA-376, most of the implementation specifics are in Part 4.

This ends the tutorial for now, you can proceed to the Simple usage section

Watch Now This tutorial has a related video course created by the Real Python team. Watch it together with the written tutorial to deepen your understanding: Editing Excel Spreadsheets in Python With openpyxl

Excel spreadsheets are one of those things you might have to deal with at some point. Either it’s because your boss loves them or because marketing needs them, you might have to learn how to work with spreadsheets, and that’s when knowing openpyxl comes in handy!

Spreadsheets are a very intuitive and user-friendly way to manipulate large datasets without any prior technical background. That’s why they’re still so commonly used today.

In this article, you’ll learn how to use openpyxl to:

  • Manipulate Excel spreadsheets with confidence
  • Extract information from spreadsheets
  • Create simple or more complex spreadsheets, including adding styles, charts, and so on

This article is written for intermediate developers who have a pretty good knowledge of Python data structures, such as dicts and lists, but also feel comfortable around OOP and more intermediate level topics.

Before You Begin

If you ever get asked to extract some data from a database or log file into an Excel spreadsheet, or if you often have to convert an Excel spreadsheet into some more usable programmatic form, then this tutorial is perfect for you. Let’s jump into the openpyxl caravan!

Practical Use Cases

First things first, when would you need to use a package like openpyxl in a real-world scenario? You’ll see a few examples below, but really, there are hundreds of possible scenarios where this knowledge could come in handy.

Importing New Products Into a Database

You are responsible for tech in an online store company, and your boss doesn’t want to pay for a cool and expensive CMS system.

Every time they want to add new products to the online store, they come to you with an Excel spreadsheet with a few hundred rows and, for each of them, you have the product name, description, price, and so forth.

Now, to import the data, you’ll have to iterate over each spreadsheet row and add each product to the online store.

Exporting Database Data Into a Spreadsheet

Say you have a Database table where you record all your users’ information, including name, phone number, email address, and so forth.

Now, the Marketing team wants to contact all users to give them some discounted offer or promotion. However, they don’t have access to the Database, or they don’t know how to use SQL to extract that information easily.

What can you do to help? Well, you can make a quick script using openpyxl that iterates over every single User record and puts all the essential information into an Excel spreadsheet.

That’s gonna earn you an extra slice of cake at your company’s next birthday party!

Appending Information to an Existing Spreadsheet

You may also have to open a spreadsheet, read the information in it and, according to some business logic, append more data to it.

For example, using the online store scenario again, say you get an Excel spreadsheet with a list of users and you need to append to each row the total amount they’ve spent in your store.

This data is in the Database and, in order to do this, you have to read the spreadsheet, iterate through each row, fetch the total amount spent from the Database and then write back to the spreadsheet.

Not a problem for openpyxl!

Learning Some Basic Excel Terminology

Here’s a quick list of basic terms you’ll see when you’re working with Excel spreadsheets:

Term Explanation
Spreadsheet or Workbook A Spreadsheet is the main file you are creating or working with.
Worksheet or Sheet A Sheet is used to split different kinds of content within the same spreadsheet. A Spreadsheet can have one or more Sheets.
Column A Column is a vertical line, and it’s represented by an uppercase letter: A.
Row A Row is a horizontal line, and it’s represented by a number: 1.
Cell A Cell is a combination of Column and Row, represented by both an uppercase letter and a number: A1.

Getting Started With openpyxl

Now that you’re aware of the benefits of a tool like openpyxl, let’s get down to it and start by installing the package. For this tutorial, you should use Python 3.7 and openpyxl 2.6.2. To install the package, you can do the following:

After you install the package, you should be able to create a super simple spreadsheet with the following code:

from openpyxl import Workbook

workbook = Workbook()
sheet = workbook.active

sheet["A1"] = "hello"
sheet["B1"] = "world!"

workbook.save(filename="hello_world.xlsx")

The code above should create a file called hello_world.xlsx in the folder you are using to run the code. If you open that file with Excel you should see something like this:

A Simple Hello World Spreadsheet

Woohoo, your first spreadsheet created!

Reading Excel Spreadsheets With openpyxl

Let’s start with the most essential thing one can do with a spreadsheet: read it.

You’ll go from a straightforward approach to reading a spreadsheet to more complex examples where you read the data and convert it into more useful Python structures.

Dataset for This Tutorial

Before you dive deep into some code examples, you should download this sample dataset and store it somewhere as sample.xlsx:

This is one of the datasets you’ll be using throughout this tutorial, and it’s a spreadsheet with a sample of real data from Amazon’s online product reviews. This dataset is only a tiny fraction of what Amazon provides, but for testing purposes, it’s more than enough.

A Simple Approach to Reading an Excel Spreadsheet

Finally, let’s start reading some spreadsheets! To begin with, open our sample spreadsheet:

>>>

>>> from openpyxl import load_workbook
>>> workbook = load_workbook(filename="sample.xlsx")
>>> workbook.sheetnames
['Sheet 1']

>>> sheet = workbook.active
>>> sheet
<Worksheet "Sheet 1">

>>> sheet.title
'Sheet 1'

In the code above, you first open the spreadsheet sample.xlsx using load_workbook(), and then you can use workbook.sheetnames to see all the sheets you have available to work with. After that, workbook.active selects the first available sheet and, in this case, you can see that it selects Sheet 1 automatically. Using these methods is the default way of opening a spreadsheet, and you’ll see it many times during this tutorial.

Now, after opening a spreadsheet, you can easily retrieve data from it like this:

>>>

>>> sheet["A1"]
<Cell 'Sheet 1'.A1>

>>> sheet["A1"].value
'marketplace'

>>> sheet["F10"].value
"G-Shock Men's Grey Sport Watch"

To return the actual value of a cell, you need to do .value. Otherwise, you’ll get the main Cell object. You can also use the method .cell() to retrieve a cell using index notation. Remember to add .value to get the actual value and not a Cell object:

>>>

>>> sheet.cell(row=10, column=6)
<Cell 'Sheet 1'.F10>

>>> sheet.cell(row=10, column=6).value
"G-Shock Men's Grey Sport Watch"

You can see that the results returned are the same, no matter which way you decide to go with. However, in this tutorial, you’ll be mostly using the first approach: ["A1"].

The above shows you the quickest way to open a spreadsheet. However, you can pass additional parameters to change the way a spreadsheet is loaded.

Additional Reading Options

There are a few arguments you can pass to load_workbook() that change the way a spreadsheet is loaded. The most important ones are the following two Booleans:

  1. read_only loads a spreadsheet in read-only mode allowing you to open very large Excel files.
  2. data_only ignores loading formulas and instead loads only the resulting values.

Importing Data From a Spreadsheet

Now that you’ve learned the basics about loading a spreadsheet, it’s about time you get to the fun part: the iteration and actual usage of the values within the spreadsheet.

This section is where you’ll learn all the different ways you can iterate through the data, but also how to convert that data into something usable and, more importantly, how to do it in a Pythonic way.

Iterating Through the Data

There are a few different ways you can iterate through the data depending on your needs.

You can slice the data with a combination of columns and rows:

>>>

>>> sheet["A1:C2"]
((<Cell 'Sheet 1'.A1>, <Cell 'Sheet 1'.B1>, <Cell 'Sheet 1'.C1>),
 (<Cell 'Sheet 1'.A2>, <Cell 'Sheet 1'.B2>, <Cell 'Sheet 1'.C2>))

You can get ranges of rows or columns:

>>>

>>> # Get all cells from column A
>>> sheet["A"]
(<Cell 'Sheet 1'.A1>,
 <Cell 'Sheet 1'.A2>,
 ...
 <Cell 'Sheet 1'.A99>,
 <Cell 'Sheet 1'.A100>)

>>> # Get all cells for a range of columns
>>> sheet["A:B"]
((<Cell 'Sheet 1'.A1>,
  <Cell 'Sheet 1'.A2>,
  ...
  <Cell 'Sheet 1'.A99>,
  <Cell 'Sheet 1'.A100>),
 (<Cell 'Sheet 1'.B1>,
  <Cell 'Sheet 1'.B2>,
  ...
  <Cell 'Sheet 1'.B99>,
  <Cell 'Sheet 1'.B100>))

>>> # Get all cells from row 5
>>> sheet[5]
(<Cell 'Sheet 1'.A5>,
 <Cell 'Sheet 1'.B5>,
 ...
 <Cell 'Sheet 1'.N5>,
 <Cell 'Sheet 1'.O5>)

>>> # Get all cells for a range of rows
>>> sheet[5:6]
((<Cell 'Sheet 1'.A5>,
  <Cell 'Sheet 1'.B5>,
  ...
  <Cell 'Sheet 1'.N5>,
  <Cell 'Sheet 1'.O5>),
 (<Cell 'Sheet 1'.A6>,
  <Cell 'Sheet 1'.B6>,
  ...
  <Cell 'Sheet 1'.N6>,
  <Cell 'Sheet 1'.O6>))

You’ll notice that all of the above examples return a tuple. If you want to refresh your memory on how to handle tuples in Python, check out the article on Lists and Tuples in Python.

There are also multiple ways of using normal Python generators to go through the data. The main methods you can use to achieve this are:

  • .iter_rows()
  • .iter_cols()

Both methods can receive the following arguments:

  • min_row
  • max_row
  • min_col
  • max_col

These arguments are used to set boundaries for the iteration:

>>>

>>> for row in sheet.iter_rows(min_row=1,
...                            max_row=2,
...                            min_col=1,
...                            max_col=3):
...     print(row)
(<Cell 'Sheet 1'.A1>, <Cell 'Sheet 1'.B1>, <Cell 'Sheet 1'.C1>)
(<Cell 'Sheet 1'.A2>, <Cell 'Sheet 1'.B2>, <Cell 'Sheet 1'.C2>)


>>> for column in sheet.iter_cols(min_row=1,
...                               max_row=2,
...                               min_col=1,
...                               max_col=3):
...     print(column)
(<Cell 'Sheet 1'.A1>, <Cell 'Sheet 1'.A2>)
(<Cell 'Sheet 1'.B1>, <Cell 'Sheet 1'.B2>)
(<Cell 'Sheet 1'.C1>, <Cell 'Sheet 1'.C2>)

You’ll notice that in the first example, when iterating through the rows using .iter_rows(), you get one tuple element per row selected. While when using .iter_cols() and iterating through columns, you’ll get one tuple per column instead.

One additional argument you can pass to both methods is the Boolean values_only. When it’s set to True, the values of the cell are returned, instead of the Cell object:

>>>

>>> for value in sheet.iter_rows(min_row=1,
...                              max_row=2,
...                              min_col=1,
...                              max_col=3,
...                              values_only=True):
...     print(value)
('marketplace', 'customer_id', 'review_id')
('US', 3653882, 'R3O9SGZBVQBV76')

If you want to iterate through the whole dataset, then you can also use the attributes .rows or .columns directly, which are shortcuts to using .iter_rows() and .iter_cols() without any arguments:

>>>

>>> for row in sheet.rows:
...     print(row)
(<Cell 'Sheet 1'.A1>, <Cell 'Sheet 1'.B1>, <Cell 'Sheet 1'.C1>
...
<Cell 'Sheet 1'.M100>, <Cell 'Sheet 1'.N100>, <Cell 'Sheet 1'.O100>)

These shortcuts are very useful when you’re iterating through the whole dataset.

Manipulate Data Using Python’s Default Data Structures

Now that you know the basics of iterating through the data in a workbook, let’s look at smart ways of converting that data into Python structures.

As you saw earlier, the result from all iterations comes in the form of tuples. However, since a tuple is nothing more than an immutable list, you can easily access its data and transform it into other structures.

For example, say you want to extract product information from the sample.xlsx spreadsheet and into a dictionary where each key is a product ID.

A straightforward way to do this is to iterate over all the rows, pick the columns you know are related to product information, and then store that in a dictionary. Let’s code this out!

First of all, have a look at the headers and see what information you care most about:

>>>

>>> for value in sheet.iter_rows(min_row=1,
...                              max_row=1,
...                              values_only=True):
...     print(value)
('marketplace', 'customer_id', 'review_id', 'product_id', ...)

This code returns a list of all the column names you have in the spreadsheet. To start, grab the columns with names:

  • product_id
  • product_parent
  • product_title
  • product_category

Lucky for you, the columns you need are all next to each other so you can use the min_column and max_column to easily get the data you want:

>>>

>>> for value in sheet.iter_rows(min_row=2,
...                              min_col=4,
...                              max_col=7,
...                              values_only=True):
...     print(value)
('B00FALQ1ZC', 937001370, 'Invicta Women's 15150 "Angel" 18k Yellow...)
('B00D3RGO20', 484010722, "Kenneth Cole New York Women's KC4944...)
...

Nice! Now that you know how to get all the important product information you need, let’s put that data into a dictionary:

import json
from openpyxl import load_workbook

workbook = load_workbook(filename="sample.xlsx")
sheet = workbook.active

products = {}

# Using the values_only because you want to return the cells' values
for row in sheet.iter_rows(min_row=2,
                           min_col=4,
                           max_col=7,
                           values_only=True):
    product_id = row[0]
    product = {
        "parent": row[1],
        "title": row[2],
        "category": row[3]
    }
    products[product_id] = product

# Using json here to be able to format the output for displaying later
print(json.dumps(products))

The code above returns a JSON similar to this:

{
  "B00FALQ1ZC": {
    "parent": 937001370,
    "title": "Invicta Women's 15150 ...",
    "category": "Watches"
  },
  "B00D3RGO20": {
    "parent": 484010722,
    "title": "Kenneth Cole New York ...",
    "category": "Watches"
  }
}

Here you can see that the output is trimmed to 2 products only, but if you run the script as it is, then you should get 98 products.

Convert Data Into Python Classes

To finalize the reading section of this tutorial, let’s dive into Python classes and see how you could improve on the example above and better structure the data.

For this, you’ll be using the new Python Data Classes that are available from Python 3.7. If you’re using an older version of Python, then you can use the default Classes instead.

So, first things first, let’s look at the data you have and decide what you want to store and how you want to store it.

As you saw right at the start, this data comes from Amazon, and it’s a list of product reviews. You can check the list of all the columns and their meaning on Amazon.

There are two significant elements you can extract from the data available:

  1. Products
  2. Reviews

A Product has:

  • ID
  • Title
  • Parent
  • Category

The Review has a few more fields:

  • ID
  • Customer ID
  • Stars
  • Headline
  • Body
  • Date

You can ignore a few of the review fields to make things a bit simpler.

So, a straightforward implementation of these two classes could be written in a separate file classes.py:

import datetime
from dataclasses import dataclass

@dataclass
class Product:
    id: str
    parent: str
    title: str
    category: str

@dataclass
class Review:
    id: str
    customer_id: str
    stars: int
    headline: str
    body: str
    date: datetime.datetime

After defining your data classes, you need to convert the data from the spreadsheet into these new structures.

Before doing the conversion, it’s worth looking at our header again and creating a mapping between columns and the fields you need:

>>>

>>> for value in sheet.iter_rows(min_row=1,
...                              max_row=1,
...                              values_only=True):
...     print(value)
('marketplace', 'customer_id', 'review_id', 'product_id', ...)

>>> # Or an alternative
>>> for cell in sheet[1]:
...     print(cell.value)
marketplace
customer_id
review_id
product_id
product_parent
...

Let’s create a file mapping.py where you have a list of all the field names and their column location (zero-indexed) on the spreadsheet:

# Product fields
PRODUCT_ID = 3
PRODUCT_PARENT = 4
PRODUCT_TITLE = 5
PRODUCT_CATEGORY = 6

# Review fields
REVIEW_ID = 2
REVIEW_CUSTOMER = 1
REVIEW_STARS = 7
REVIEW_HEADLINE = 12
REVIEW_BODY = 13
REVIEW_DATE = 14

You don’t necessarily have to do the mapping above. It’s more for readability when parsing the row data, so you don’t end up with a lot of magic numbers lying around.

Finally, let’s look at the code needed to parse the spreadsheet data into a list of product and review objects:

from datetime import datetime
from openpyxl import load_workbook
from classes import Product, Review
from mapping import PRODUCT_ID, PRODUCT_PARENT, PRODUCT_TITLE, 
    PRODUCT_CATEGORY, REVIEW_DATE, REVIEW_ID, REVIEW_CUSTOMER, 
    REVIEW_STARS, REVIEW_HEADLINE, REVIEW_BODY

# Using the read_only method since you're not gonna be editing the spreadsheet
workbook = load_workbook(filename="sample.xlsx", read_only=True)
sheet = workbook.active

products = []
reviews = []

# Using the values_only because you just want to return the cell value
for row in sheet.iter_rows(min_row=2, values_only=True):
    product = Product(id=row[PRODUCT_ID],
                      parent=row[PRODUCT_PARENT],
                      title=row[PRODUCT_TITLE],
                      category=row[PRODUCT_CATEGORY])
    products.append(product)

    # You need to parse the date from the spreadsheet into a datetime format
    spread_date = row[REVIEW_DATE]
    parsed_date = datetime.strptime(spread_date, "%Y-%m-%d")

    review = Review(id=row[REVIEW_ID],
                    customer_id=row[REVIEW_CUSTOMER],
                    stars=row[REVIEW_STARS],
                    headline=row[REVIEW_HEADLINE],
                    body=row[REVIEW_BODY],
                    date=parsed_date)
    reviews.append(review)

print(products[0])
print(reviews[0])

After you run the code above, you should get some output like this:

Product(id='B00FALQ1ZC', parent=937001370, ...)
Review(id='R3O9SGZBVQBV76', customer_id=3653882, ...)

That’s it! Now you should have the data in a very simple and digestible class format, and you can start thinking of storing this in a Database or any other type of data storage you like.

Using this kind of OOP strategy to parse spreadsheets makes handling the data much simpler later on.

Appending New Data

Before you start creating very complex spreadsheets, have a quick look at an example of how to append data to an existing spreadsheet.

Go back to the first example spreadsheet you created (hello_world.xlsx) and try opening it and appending some data to it, like this:

from openpyxl import load_workbook

# Start by opening the spreadsheet and selecting the main sheet
workbook = load_workbook(filename="hello_world.xlsx")
sheet = workbook.active

# Write what you want into a specific cell
sheet["C1"] = "writing ;)"

# Save the spreadsheet
workbook.save(filename="hello_world_append.xlsx")

Et voilà, if you open the new hello_world_append.xlsx spreadsheet, you’ll see the following change:

Appending Data to a Spreadsheet

Notice the additional writing ;) on cell C1.

Writing Excel Spreadsheets With openpyxl

There are a lot of different things you can write to a spreadsheet, from simple text or number values to complex formulas, charts, or even images.

Let’s start creating some spreadsheets!

Creating a Simple Spreadsheet

Previously, you saw a very quick example of how to write “Hello world!” into a spreadsheet, so you can start with that:

 1from openpyxl import Workbook
 2
 3filename = "hello_world.xlsx"
 4
 5workbook = Workbook()
 6sheet = workbook.active
 7
 8sheet["A1"] = "hello"
 9sheet["B1"] = "world!"
10
11workbook.save(filename=filename)

The highlighted lines in the code above are the most important ones for writing. In the code, you can see that:

  • Line 5 shows you how to create a new empty workbook.
  • Lines 8 and 9 show you how to add data to specific cells.
  • Line 11 shows you how to save the spreadsheet when you’re done.

Even though these lines above can be straightforward, it’s still good to know them well for when things get a bit more complicated.

One thing you can do to help with coming code examples is add the following method to your Python file or console:

>>>

>>> def print_rows():
...     for row in sheet.iter_rows(values_only=True):
...         print(row)

It makes it easier to print all of your spreadsheet values by just calling print_rows().

Basic Spreadsheet Operations

Before you get into the more advanced topics, it’s good for you to know how to manage the most simple elements of a spreadsheet.

Adding and Updating Cell Values

You already learned how to add values to a spreadsheet like this:

>>>

>>> sheet["A1"] = "value"

There’s another way you can do this, by first selecting a cell and then changing its value:

>>>

>>> cell = sheet["A1"]
>>> cell
<Cell 'Sheet'.A1>

>>> cell.value
'hello'

>>> cell.value = "hey"
>>> cell.value
'hey'

The new value is only stored into the spreadsheet once you call workbook.save().

The openpyxl creates a cell when adding a value, if that cell didn’t exist before:

>>>

>>> # Before, our spreadsheet has only 1 row
>>> print_rows()
('hello', 'world!')

>>> # Try adding a value to row 10
>>> sheet["B10"] = "test"
>>> print_rows()
('hello', 'world!')
(None, None)
(None, None)
(None, None)
(None, None)
(None, None)
(None, None)
(None, None)
(None, None)
(None, 'test')

As you can see, when trying to add a value to cell B10, you end up with a tuple with 10 rows, just so you can have that test value.

Managing Rows and Columns

One of the most common things you have to do when manipulating spreadsheets is adding or removing rows and columns. The openpyxl package allows you to do that in a very straightforward way by using the methods:

  • .insert_rows()
  • .delete_rows()
  • .insert_cols()
  • .delete_cols()

Every single one of those methods can receive two arguments:

  1. idx
  2. amount

Using our basic hello_world.xlsx example again, let’s see how these methods work:

>>>

>>> print_rows()
('hello', 'world!')

>>> # Insert a column before the existing column 1 ("A")
>>> sheet.insert_cols(idx=1)
>>> print_rows()
(None, 'hello', 'world!')

>>> # Insert 5 columns between column 2 ("B") and 3 ("C")
>>> sheet.insert_cols(idx=3, amount=5)
>>> print_rows()
(None, 'hello', None, None, None, None, None, 'world!')

>>> # Delete the created columns
>>> sheet.delete_cols(idx=3, amount=5)
>>> sheet.delete_cols(idx=1)
>>> print_rows()
('hello', 'world!')

>>> # Insert a new row in the beginning
>>> sheet.insert_rows(idx=1)
>>> print_rows()
(None, None)
('hello', 'world!')

>>> # Insert 3 new rows in the beginning
>>> sheet.insert_rows(idx=1, amount=3)
>>> print_rows()
(None, None)
(None, None)
(None, None)
(None, None)
('hello', 'world!')

>>> # Delete the first 4 rows
>>> sheet.delete_rows(idx=1, amount=4)
>>> print_rows()
('hello', 'world!')

The only thing you need to remember is that when inserting new data (rows or columns), the insertion happens before the idx parameter.

So, if you do insert_rows(1), it inserts a new row before the existing first row.

It’s the same for columns: when you call insert_cols(2), it inserts a new column right before the already existing second column (B).

However, when deleting rows or columns, .delete_... deletes data starting from the index passed as an argument.

For example, when doing delete_rows(2) it deletes row 2, and when doing delete_cols(3) it deletes the third column (C).

Managing Sheets

Sheet management is also one of those things you might need to know, even though it might be something that you don’t use that often.

If you look back at the code examples from this tutorial, you’ll notice the following recurring piece of code:

This is the way to select the default sheet from a spreadsheet. However, if you’re opening a spreadsheet with multiple sheets, then you can always select a specific one like this:

>>>

>>> # Let's say you have two sheets: "Products" and "Company Sales"
>>> workbook.sheetnames
['Products', 'Company Sales']

>>> # You can select a sheet using its title
>>> products_sheet = workbook["Products"]
>>> sales_sheet = workbook["Company Sales"]

You can also change a sheet title very easily:

>>>

>>> workbook.sheetnames
['Products', 'Company Sales']

>>> products_sheet = workbook["Products"]
>>> products_sheet.title = "New Products"

>>> workbook.sheetnames
['New Products', 'Company Sales']

If you want to create or delete sheets, then you can also do that with .create_sheet() and .remove():

>>>

>>> workbook.sheetnames
['Products', 'Company Sales']

>>> operations_sheet = workbook.create_sheet("Operations")
>>> workbook.sheetnames
['Products', 'Company Sales', 'Operations']

>>> # You can also define the position to create the sheet at
>>> hr_sheet = workbook.create_sheet("HR", 0)
>>> workbook.sheetnames
['HR', 'Products', 'Company Sales', 'Operations']

>>> # To remove them, just pass the sheet as an argument to the .remove()
>>> workbook.remove(operations_sheet)
>>> workbook.sheetnames
['HR', 'Products', 'Company Sales']

>>> workbook.remove(hr_sheet)
>>> workbook.sheetnames
['Products', 'Company Sales']

One other thing you can do is make duplicates of a sheet using copy_worksheet():

>>>

>>> workbook.sheetnames
['Products', 'Company Sales']

>>> products_sheet = workbook["Products"]
>>> workbook.copy_worksheet(products_sheet)
<Worksheet "Products Copy">

>>> workbook.sheetnames
['Products', 'Company Sales', 'Products Copy']

If you open your spreadsheet after saving the above code, you’ll notice that the sheet Products Copy is a duplicate of the sheet Products.

Freezing Rows and Columns

Something that you might want to do when working with big spreadsheets is to freeze a few rows or columns, so they remain visible when you scroll right or down.

Freezing data allows you to keep an eye on important rows or columns, regardless of where you scroll in the spreadsheet.

Again, openpyxl also has a way to accomplish this by using the worksheet freeze_panes attribute. For this example, go back to our sample.xlsx spreadsheet and try doing the following:

>>>

>>> workbook = load_workbook(filename="sample.xlsx")
>>> sheet = workbook.active
>>> sheet.freeze_panes = "C2"
>>> workbook.save("sample_frozen.xlsx")

If you open the sample_frozen.xlsx spreadsheet in your favorite spreadsheet editor, you’ll notice that row 1 and columns A and B are frozen and are always visible no matter where you navigate within the spreadsheet.

This feature is handy, for example, to keep headers within sight, so you always know what each column represents.

Here’s how it looks in the editor:

Example Spreadsheet With Frozen Rows and Columns

Notice how you’re at the end of the spreadsheet, and yet, you can see both row 1 and columns A and B.

Adding Filters

You can use openpyxl to add filters and sorts to your spreadsheet. However, when you open the spreadsheet, the data won’t be rearranged according to these sorts and filters.

At first, this might seem like a pretty useless feature, but when you’re programmatically creating a spreadsheet that is going to be sent and used by somebody else, it’s still nice to at least create the filters and allow people to use it afterward.

The code below is an example of how you would add some filters to our existing sample.xlsx spreadsheet:

>>>

>>> # Check the used spreadsheet space using the attribute "dimensions"
>>> sheet.dimensions
'A1:O100'

>>> sheet.auto_filter.ref = "A1:O100"
>>> workbook.save(filename="sample_with_filters.xlsx")

You should now see the filters created when opening the spreadsheet in your editor:

Example Spreadsheet With Filters

You don’t have to use sheet.dimensions if you know precisely which part of the spreadsheet you want to apply filters to.

Adding Formulas

Formulas (or formulae) are one of the most powerful features of spreadsheets.

They gives you the power to apply specific mathematical equations to a range of cells. Using formulas with openpyxl is as simple as editing the value of a cell.

You can see the list of formulas supported by openpyxl:

>>>

>>> from openpyxl.utils import FORMULAE
>>> FORMULAE
frozenset({'ABS',
           'ACCRINT',
           'ACCRINTM',
           'ACOS',
           'ACOSH',
           'AMORDEGRC',
           'AMORLINC',
           'AND',
           ...
           'YEARFRAC',
           'YIELD',
           'YIELDDISC',
           'YIELDMAT',
           'ZTEST'})

Let’s add some formulas to our sample.xlsx spreadsheet.

Starting with something easy, let’s check the average star rating for the 99 reviews within the spreadsheet:

>>>

>>> # Star rating is column "H"
>>> sheet["P2"] = "=AVERAGE(H2:H100)"
>>> workbook.save(filename="sample_formulas.xlsx")

If you open the spreadsheet now and go to cell P2, you should see that its value is: 4.18181818181818. Have a look in the editor:

Example Spreadsheet With Average Formula

You can use the same methodology to add any formulas to your spreadsheet. For example, let’s count the number of reviews that had helpful votes:

>>>

>>> # The helpful votes are counted on column "I"
>>> sheet["P3"] = '=COUNTIF(I2:I100, ">0")'
>>> workbook.save(filename="sample_formulas.xlsx")

You should get the number 21 on your P3 spreadsheet cell like so:

Example Spreadsheet With Average and CountIf Formula

You’ll have to make sure that the strings within a formula are always in double quotes, so you either have to use single quotes around the formula like in the example above or you’ll have to escape the double quotes inside the formula: "=COUNTIF(I2:I100, ">0")".

There are a ton of other formulas you can add to your spreadsheet using the same procedure you tried above. Give it a go yourself!

Adding Styles

Even though styling a spreadsheet might not be something you would do every day, it’s still good to know how to do it.

Using openpyxl, you can apply multiple styling options to your spreadsheet, including fonts, borders, colors, and so on. Have a look at the openpyxl documentation to learn more.

You can also choose to either apply a style directly to a cell or create a template and reuse it to apply styles to multiple cells.

Let’s start by having a look at simple cell styling, using our sample.xlsx again as the base spreadsheet:

>>>

>>> # Import necessary style classes
>>> from openpyxl.styles import Font, Color, Alignment, Border, Side

>>> # Create a few styles
>>> bold_font = Font(bold=True)
>>> big_red_text = Font(color="00FF0000", size=20)
>>> center_aligned_text = Alignment(horizontal="center")
>>> double_border_side = Side(border_style="double")
>>> square_border = Border(top=double_border_side,
...                        right=double_border_side,
...                        bottom=double_border_side,
...                        left=double_border_side)

>>> # Style some cells!
>>> sheet["A2"].font = bold_font
>>> sheet["A3"].font = big_red_text
>>> sheet["A4"].alignment = center_aligned_text
>>> sheet["A5"].border = square_border
>>> workbook.save(filename="sample_styles.xlsx")

If you open your spreadsheet now, you should see quite a few different styles on the first 5 cells of column A:

Example Spreadsheet With Simple Cell Styles

There you go. You got:

  • A2 with the text in bold
  • A3 with the text in red and bigger font size
  • A4 with the text centered
  • A5 with a square border around the text

You can also combine styles by simply adding them to the cell at the same time:

>>>

>>> # Reusing the same styles from the example above
>>> sheet["A6"].alignment = center_aligned_text
>>> sheet["A6"].font = big_red_text
>>> sheet["A6"].border = square_border
>>> workbook.save(filename="sample_styles.xlsx")

Have a look at cell A6 here:

Example Spreadsheet With Coupled Cell Styles

When you want to apply multiple styles to one or several cells, you can use a NamedStyle class instead, which is like a style template that you can use over and over again. Have a look at the example below:

>>>

>>> from openpyxl.styles import NamedStyle

>>> # Let's create a style template for the header row
>>> header = NamedStyle(name="header")
>>> header.font = Font(bold=True)
>>> header.border = Border(bottom=Side(border_style="thin"))
>>> header.alignment = Alignment(horizontal="center", vertical="center")

>>> # Now let's apply this to all first row (header) cells
>>> header_row = sheet[1]
>>> for cell in header_row:
...     cell.style = header

>>> workbook.save(filename="sample_styles.xlsx")

If you open the spreadsheet now, you should see that its first row is bold, the text is aligned to the center, and there’s a small bottom border! Have a look below:

Example Spreadsheet With Named Styles

As you saw above, there are many options when it comes to styling, and it depends on the use case, so feel free to check openpyxl documentation and see what other things you can do.

Conditional Formatting

This feature is one of my personal favorites when it comes to adding styles to a spreadsheet.

It’s a much more powerful approach to styling because it dynamically applies styles according to how the data in the spreadsheet changes.

In a nutshell, conditional formatting allows you to specify a list of styles to apply to a cell (or cell range) according to specific conditions.

For example, a widespread use case is to have a balance sheet where all the negative totals are in red, and the positive ones are in green. This formatting makes it much more efficient to spot good vs bad periods.

Without further ado, let’s pick our favorite spreadsheet—sample.xlsx—and add some conditional formatting.

You can start by adding a simple one that adds a red background to all reviews with less than 3 stars:

>>>

>>> from openpyxl.styles import PatternFill
>>> from openpyxl.styles.differential import DifferentialStyle
>>> from openpyxl.formatting.rule import Rule

>>> red_background = PatternFill(fgColor="00FF0000")
>>> diff_style = DifferentialStyle(fill=red_background)
>>> rule = Rule(type="expression", dxf=diff_style)
>>> rule.formula = ["$H1<3"]
>>> sheet.conditional_formatting.add("A1:O100", rule)
>>> workbook.save("sample_conditional_formatting.xlsx")

Now you’ll see all the reviews with a star rating below 3 marked with a red background:

Example Spreadsheet With Simple Conditional Formatting

Code-wise, the only things that are new here are the objects DifferentialStyle and Rule:

  • DifferentialStyle is quite similar to NamedStyle, which you already saw above, and it’s used to aggregate multiple styles such as fonts, borders, alignment, and so forth.
  • Rule is responsible for selecting the cells and applying the styles if the cells match the rule’s logic.

Using a Rule object, you can create numerous conditional formatting scenarios.

However, for simplicity sake, the openpyxl package offers 3 built-in formats that make it easier to create a few common conditional formatting patterns. These built-ins are:

  • ColorScale
  • IconSet
  • DataBar

The ColorScale gives you the ability to create color gradients:

>>>

>>> from openpyxl.formatting.rule import ColorScaleRule
>>> color_scale_rule = ColorScaleRule(start_type="min",
...                                   start_color="00FF0000",  # Red
...                                   end_type="max",
...                                   end_color="0000FF00")  # Green

>>> # Again, let's add this gradient to the star ratings, column "H"
>>> sheet.conditional_formatting.add("H2:H100", color_scale_rule)
>>> workbook.save(filename="sample_conditional_formatting_color_scale.xlsx")

Now you should see a color gradient on column H, from red to green, according to the star rating:

Example Spreadsheet With Color Scale Conditional Formatting

You can also add a third color and make two gradients instead:

>>>

>>> from openpyxl.formatting.rule import ColorScaleRule
>>> color_scale_rule = ColorScaleRule(start_type="num",
...                                   start_value=1,
...                                   start_color="00FF0000",  # Red
...                                   mid_type="num",
...                                   mid_value=3,
...                                   mid_color="00FFFF00",  # Yellow
...                                   end_type="num",
...                                   end_value=5,
...                                   end_color="0000FF00")  # Green

>>> # Again, let's add this gradient to the star ratings, column "H"
>>> sheet.conditional_formatting.add("H2:H100", color_scale_rule)
>>> workbook.save(filename="sample_conditional_formatting_color_scale_3.xlsx")

This time, you’ll notice that star ratings between 1 and 3 have a gradient from red to yellow, and star ratings between 3 and 5 have a gradient from yellow to green:

Example Spreadsheet With 2 Color Scales Conditional Formatting

The IconSet allows you to add an icon to the cell according to its value:

>>>

>>> from openpyxl.formatting.rule import IconSetRule

>>> icon_set_rule = IconSetRule("5Arrows", "num", [1, 2, 3, 4, 5])
>>> sheet.conditional_formatting.add("H2:H100", icon_set_rule)
>>> workbook.save("sample_conditional_formatting_icon_set.xlsx")

You’ll see a colored arrow next to the star rating. This arrow is red and points down when the value of the cell is 1 and, as the rating gets better, the arrow starts pointing up and becomes green:

Example Spreadsheet With Icon Set Conditional Formatting

The openpyxl package has a full list of other icons you can use, besides the arrow.

Finally, the DataBar allows you to create progress bars:

>>>

>>> from openpyxl.formatting.rule import DataBarRule

>>> data_bar_rule = DataBarRule(start_type="num",
...                             start_value=1,
...                             end_type="num",
...                             end_value="5",
...                             color="0000FF00")  # Green
>>> sheet.conditional_formatting.add("H2:H100", data_bar_rule)
>>> workbook.save("sample_conditional_formatting_data_bar.xlsx")

You’ll now see a green progress bar that gets fuller the closer the star rating is to the number 5:

Example Spreadsheet With Data Bar Conditional Formatting

As you can see, there are a lot of cool things you can do with conditional formatting.

Here, you saw only a few examples of what you can achieve with it, but check the openpyxl documentation to see a bunch of other options.

Adding Images

Even though images are not something that you’ll often see in a spreadsheet, it’s quite cool to be able to add them. Maybe you can use it for branding purposes or to make spreadsheets more personal.

To be able to load images to a spreadsheet using openpyxl, you’ll have to install Pillow:

Apart from that, you’ll also need an image. For this example, you can grab the Real Python logo below and convert it from .webp to .png using an online converter such as cloudconvert.com, save the final file as logo.png, and copy it to the root folder where you’re running your examples:

Real Python Logo

Afterward, this is the code you need to import that image into the hello_word.xlsx spreadsheet:

from openpyxl import load_workbook
from openpyxl.drawing.image import Image

# Let's use the hello_world spreadsheet since it has less data
workbook = load_workbook(filename="hello_world.xlsx")
sheet = workbook.active

logo = Image("logo.png")

# A bit of resizing to not fill the whole spreadsheet with the logo
logo.height = 150
logo.width = 150

sheet.add_image(logo, "A3")
workbook.save(filename="hello_world_logo.xlsx")

You have an image on your spreadsheet! Here it is:

Example Spreadsheet With Image

The image’s left top corner is on the cell you chose, in this case, A3.

Adding Pretty Charts

Another powerful thing you can do with spreadsheets is create an incredible variety of charts.

Charts are a great way to visualize and understand loads of data quickly. There are a lot of different chart types: bar chart, pie chart, line chart, and so on. openpyxl has support for a lot of them.

Here, you’ll see only a couple of examples of charts because the theory behind it is the same for every single chart type:

For any chart you want to build, you’ll need to define the chart type: BarChart, LineChart, and so forth, plus the data to be used for the chart, which is called Reference.

Before you can build your chart, you need to define what data you want to see represented in it. Sometimes, you can use the dataset as is, but other times you need to massage the data a bit to get additional information.

Let’s start by building a new workbook with some sample data:

 1from openpyxl import Workbook
 2from openpyxl.chart import BarChart, Reference
 3
 4workbook = Workbook()
 5sheet = workbook.active
 6
 7# Let's create some sample sales data
 8rows = [
 9    ["Product", "Online", "Store"],
10    [1, 30, 45],
11    [2, 40, 30],
12    [3, 40, 25],
13    [4, 50, 30],
14    [5, 30, 25],
15    [6, 25, 35],
16    [7, 20, 40],
17]
18
19for row in rows:
20    sheet.append(row)

Now you’re going to start by creating a bar chart that displays the total number of sales per product:

22chart = BarChart()
23data = Reference(worksheet=sheet,
24                 min_row=1,
25                 max_row=8,
26                 min_col=2,
27                 max_col=3)
28
29chart.add_data(data, titles_from_data=True)
30sheet.add_chart(chart, "E2")
31
32workbook.save("chart.xlsx")

There you have it. Below, you can see a very straightforward bar chart showing the difference between online product sales online and in-store product sales:

Example Spreadsheet With Bar Chart

Like with images, the top left corner of the chart is on the cell you added the chart to. In your case, it was on cell E2.

Try creating a line chart instead, changing the data a bit:

 1import random
 2from openpyxl import Workbook
 3from openpyxl.chart import LineChart, Reference
 4
 5workbook = Workbook()
 6sheet = workbook.active
 7
 8# Let's create some sample sales data
 9rows = [
10    ["", "January", "February", "March", "April",
11    "May", "June", "July", "August", "September",
12     "October", "November", "December"],
13    [1, ],
14    [2, ],
15    [3, ],
16]
17
18for row in rows:
19    sheet.append(row)
20
21for row in sheet.iter_rows(min_row=2,
22                           max_row=4,
23                           min_col=2,
24                           max_col=13):
25    for cell in row:
26        cell.value = random.randrange(5, 100)

With the above code, you’ll be able to generate some random data regarding the sales of 3 different products across a whole year.

Once that’s done, you can very easily create a line chart with the following code:

28chart = LineChart()
29data = Reference(worksheet=sheet,
30                 min_row=2,
31                 max_row=4,
32                 min_col=1,
33                 max_col=13)
34
35chart.add_data(data, from_rows=True, titles_from_data=True)
36sheet.add_chart(chart, "C6")
37
38workbook.save("line_chart.xlsx")

Here’s the outcome of the above piece of code:

Example Spreadsheet With Line Chart

One thing to keep in mind here is the fact that you’re using from_rows=True when adding the data. This argument makes the chart plot row by row instead of column by column.

In your sample data, you see that each product has a row with 12 values (1 column per month). That’s why you use from_rows. If you don’t pass that argument, by default, the chart tries to plot by column, and you’ll get a month-by-month comparison of sales.

Another difference that has to do with the above argument change is the fact that our Reference now starts from the first column, min_col=1, instead of the second one. This change is needed because the chart now expects the first column to have the titles.

There are a couple of other things you can also change regarding the style of the chart. For example, you can add specific categories to the chart:

cats = Reference(worksheet=sheet,
                 min_row=1,
                 max_row=1,
                 min_col=2,
                 max_col=13)
chart.set_categories(cats)

Add this piece of code before saving the workbook, and you should see the month names appearing instead of numbers:

Example Spreadsheet With Line Chart and Categories

Code-wise, this is a minimal change. But in terms of the readability of the spreadsheet, this makes it much easier for someone to open the spreadsheet and understand the chart straight away.

Another thing you can do to improve the chart readability is to add an axis. You can do it using the attributes x_axis and y_axis:

chart.x_axis.title = "Months"
chart.y_axis.title = "Sales (per unit)"

This will generate a spreadsheet like the below one:

Example Spreadsheet With Line Chart, Categories and Axis Titles

As you can see, small changes like the above make reading your chart a much easier and quicker task.

There is also a way to style your chart by using Excel’s default ChartStyle property. In this case, you have to choose a number between 1 and 48. Depending on your choice, the colors of your chart change as well:

# You can play with this by choosing any number between 1 and 48
chart.style = 24

With the style selected above, all lines have some shade of orange:

Example Spreadsheet With Line Chart, Categories, Axis Titles and Style

There is no clear documentation on what each style number looks like, but this spreadsheet has a few examples of the styles available.

Here’s the full code used to generate the line chart with categories, axis titles, and style:

import random
from openpyxl import Workbook
from openpyxl.chart import LineChart, Reference

workbook = Workbook()
sheet = workbook.active

# Let's create some sample sales data
rows = [
    ["", "January", "February", "March", "April",
    "May", "June", "July", "August", "September",
     "October", "November", "December"],
    [1, ],
    [2, ],
    [3, ],
]

for row in rows:
    sheet.append(row)

for row in sheet.iter_rows(min_row=2,
                           max_row=4,
                           min_col=2,
                           max_col=13):
    for cell in row:
        cell.value = random.randrange(5, 100)

# Create a LineChart and add the main data
chart = LineChart()
data = Reference(worksheet=sheet,
                           min_row=2,
                           max_row=4,
                           min_col=1,
                           max_col=13)
chart.add_data(data, titles_from_data=True, from_rows=True)

# Add categories to the chart
cats = Reference(worksheet=sheet,
                 min_row=1,
                 max_row=1,
                 min_col=2,
                 max_col=13)
chart.set_categories(cats)

# Rename the X and Y Axis
chart.x_axis.title = "Months"
chart.y_axis.title = "Sales (per unit)"

# Apply a specific Style
chart.style = 24

# Save!
sheet.add_chart(chart, "C6")
workbook.save("line_chart.xlsx")

There are a lot more chart types and customization you can apply, so be sure to check out the package documentation on this if you need some specific formatting.

Convert Python Classes to Excel Spreadsheet

You already saw how to convert an Excel spreadsheet’s data into Python classes, but now let’s do the opposite.

Let’s imagine you have a database and are using some Object-Relational Mapping (ORM) to map DB objects into Python classes. Now, you want to export those same objects into a spreadsheet.

Let’s assume the following data classes to represent the data coming from your database regarding product sales:

from dataclasses import dataclass
from typing import List

@dataclass
class Sale:
    quantity: int

@dataclass
class Product:
    id: str
    name: str
    sales: List[Sale]

Now, let’s generate some random data, assuming the above classes are stored in a db_classes.py file:

 1import random
 2
 3# Ignore these for now. You'll use them in a sec ;)
 4from openpyxl import Workbook
 5from openpyxl.chart import LineChart, Reference
 6
 7from db_classes import Product, Sale
 8
 9products = []
10
11# Let's create 5 products
12for idx in range(1, 6):
13    sales = []
14
15    # Create 5 months of sales
16    for _ in range(5):
17        sale = Sale(quantity=random.randrange(5, 100))
18        sales.append(sale)
19
20    product = Product(id=str(idx),
21                      name="Product %s" % idx,
22                      sales=sales)
23    products.append(product)

By running this piece of code, you should get 5 products with 5 months of sales with a random quantity of sales for each month.

Now, to convert this into a spreadsheet, you need to iterate over the data and append it to the spreadsheet:

25workbook = Workbook()
26sheet = workbook.active
27
28# Append column names first
29sheet.append(["Product ID", "Product Name", "Month 1",
30              "Month 2", "Month 3", "Month 4", "Month 5"])
31
32# Append the data
33for product in products:
34    data = [product.id, product.name]
35    for sale in product.sales:
36        data.append(sale.quantity)
37    sheet.append(data)

That’s it. That should allow you to create a spreadsheet with some data coming from your database.

However, why not use some of that cool knowledge you gained recently to add a chart as well to display that data more visually?

All right, then you could probably do something like this:

38chart = LineChart()
39data = Reference(worksheet=sheet,
40                 min_row=2,
41                 max_row=6,
42                 min_col=2,
43                 max_col=7)
44
45chart.add_data(data, titles_from_data=True, from_rows=True)
46sheet.add_chart(chart, "B8")
47
48cats = Reference(worksheet=sheet,
49                 min_row=1,
50                 max_row=1,
51                 min_col=3,
52                 max_col=7)
53chart.set_categories(cats)
54
55chart.x_axis.title = "Months"
56chart.y_axis.title = "Sales (per unit)"
57
58workbook.save(filename="oop_sample.xlsx")

Now we’re talking! Here’s a spreadsheet generated from database objects and with a chart and everything:

Example Spreadsheet With Conversion from Python Data Classes

That’s a great way for you to wrap up your new knowledge of charts!

Bonus: Working With Pandas

Even though you can use Pandas to handle Excel files, there are few things that you either can’t accomplish with Pandas or that you’d be better off just using openpyxl directly.

For example, some of the advantages of using openpyxl are the ability to easily customize your spreadsheet with styles, conditional formatting, and such.

But guess what, you don’t have to worry about picking. In fact, openpyxl has support for both converting data from a Pandas DataFrame into a workbook or the opposite, converting an openpyxl workbook into a Pandas DataFrame.

First things first, remember to install the pandas package:

Then, let’s create a sample DataFrame:

 1import pandas as pd
 2
 3data = {
 4    "Product Name": ["Product 1", "Product 2"],
 5    "Sales Month 1": [10, 20],
 6    "Sales Month 2": [5, 35],
 7}
 8df = pd.DataFrame(data)

Now that you have some data, you can use .dataframe_to_rows() to convert it from a DataFrame into a worksheet:

10from openpyxl import Workbook
11from openpyxl.utils.dataframe import dataframe_to_rows
12
13workbook = Workbook()
14sheet = workbook.active
15
16for row in dataframe_to_rows(df, index=False, header=True):
17    sheet.append(row)
18
19workbook.save("pandas.xlsx")

You should see a spreadsheet that looks like this:

Example Spreadsheet With Data from Pandas Data Frame

If you want to add the DataFrame’s index, you can change index=True, and it adds each row’s index into your spreadsheet.

On the other hand, if you want to convert a spreadsheet into a DataFrame, you can also do it in a very straightforward way like so:

import pandas as pd
from openpyxl import load_workbook

workbook = load_workbook(filename="sample.xlsx")
sheet = workbook.active

values = sheet.values
df = pd.DataFrame(values)

Alternatively, if you want to add the correct headers and use the review ID as the index, for example, then you can also do it like this instead:

import pandas as pd
from openpyxl import load_workbook
from mapping import REVIEW_ID

workbook = load_workbook(filename="sample.xlsx")
sheet = workbook.active

data = sheet.values

# Set the first row as the columns for the DataFrame
cols = next(data)
data = list(data)

# Set the field "review_id" as the indexes for each row
idx = [row[REVIEW_ID] for row in data]

df = pd.DataFrame(data, index=idx, columns=cols)

Using indexes and columns allows you to access data from your DataFrame easily:

>>>

>>> df.columns
Index(['marketplace', 'customer_id', 'review_id', 'product_id',
       'product_parent', 'product_title', 'product_category', 'star_rating',
       'helpful_votes', 'total_votes', 'vine', 'verified_purchase',
       'review_headline', 'review_body', 'review_date'],
      dtype='object')

>>> # Get first 10 reviews' star rating
>>> df["star_rating"][:10]
R3O9SGZBVQBV76    5
RKH8BNC3L5DLF     5
R2HLE8WKZSU3NL    2
R31U3UH5AZ42LL    5
R2SV659OUJ945Y    4
RA51CP8TR5A2L     5
RB2Q7DLDN6TH6     5
R2RHFJV0UYBK3Y    1
R2Z6JOQ94LFHEP    5
RX27XIIWY5JPB     4
Name: star_rating, dtype: int64

>>> # Grab review with id "R2EQL1V1L6E0C9", using the index
>>> df.loc["R2EQL1V1L6E0C9"]
marketplace               US
customer_id         15305006
review_id     R2EQL1V1L6E0C9
product_id        B004LURNO6
product_parent     892860326
review_headline   Five Stars
review_body          Love it
review_date       2015-08-31
Name: R2EQL1V1L6E0C9, dtype: object

There you go, whether you want to use openpyxl to prettify your Pandas dataset or use Pandas to do some hardcore algebra, you now know how to switch between both packages.

Conclusion

Phew, after that long read, you now know how to work with spreadsheets in Python! You can rely on openpyxl, your trustworthy companion, to:

  • Extract valuable information from spreadsheets in a Pythonic manner
  • Create your own spreadsheets, no matter the complexity level
  • Add cool features such as conditional formatting or charts to your spreadsheets

There are a few other things you can do with openpyxl that might not have been covered in this tutorial, but you can always check the package’s official documentation website to learn more about it. You can even venture into checking its source code and improving the package further.

Feel free to leave any comments below if you have any questions, or if there’s any section you’d love to hear more about.

Watch Now This tutorial has a related video course created by the Real Python team. Watch it together with the written tutorial to deepen your understanding: Editing Excel Spreadsheets in Python With openpyxl

Reading Excel spreadsheets is all well and good. However, you also need to be able to create or edit a spreadsheet. The focus of this chapter will be on learning how to do that! OpenPyXL lets you create Microsoft Excel spreadsheets with a minimum of fuss.

Creating Excel spreadsheets using Python allows you to generate a new type of report that your users will use. For example, you might receive your data from a client in the form of JSON or XML. These data formats are not something that most accountants or business people are used to reading.

Once you learn how to create Excel spreadsheets with Python, you can leverage that knowledge to transform other data into Excel spreadsheets. This knowledge also allows you to do the reverse, taking in an Excel spreadsheet and output a different format, such as JSON or XML.

In this article, you will learn how to use OpenPyXL to do the following:

  • Create a spreadsheet
  • Write to a spreadsheet
  • Add and remove sheets
  • Insert and delete rows and columns
  • Edit cell data
  • Create merged cells
  • Fold rows and columns

Let’s get started by creating a brand new spreadsheet!

Editor’s note: This article is based on a chapter from the book: Automating Excel with Python. You can order a copy on Gumroad or Kickstarter.

Creating a Spreadsheet

Creating an empty spreadsheet using OpenPyXL doesn’t take much code. Open up your Python editor and create a new file. Name it creating_spreadsheet.py.

Now add the following code to your file:

# creating_spreadsheet.py

from openpyxl import Workbook


def create_workbook(path):
    workbook = Workbook()
    workbook.save(path)


if __name__ == "__main__":
    create_workbook("hello.xlsx")

The critical piece here is that you need to import the Workbook class. This class allows you to instantiate a workbook object that you can then save. All this code does is create the file that you pass to it and save it.

Your new spreadsheet will look like this:

An empty Excel spreadsheet

Now you’re ready to learn how to add some data to the cells in your spreadsheet.

Writing to a Spreadsheet

When writing data in a spreadsheet, you need to get the “sheet” object. You learned how to do that in the previous chapter using workbook.active, which gives you the active or currently visible sheet. You could also explicitly tell OpenPyXL which sheet you want to access by passing it a sheet title.

For this example, you will create another new program and then use the active sheet. Open up a new file and name it adding_data.py. Now add this code to your file:

# adding_data.py

from openpyxl import Workbook


def create_workbook(path):
    workbook = Workbook()
    sheet = workbook.active
    sheet["A1"] = "Hello"
    sheet["A2"] = "from"
    sheet["A3"] = "OpenPyXL"
    workbook.save(path)


if __name__ == "__main__":
    create_workbook("hello.xlsx")

This code will overwrite the previous example’s Excel spreadsheet. After you create the Workbook() object, you grab the active Worksheet. Then you add text strings to the cells: A1, A2, and A3. The last step is to save your new spreadsheet.

When you run this code, your new spreadsheet will look like this:

Hello World Excel Spreadsheet

You can use this technique to write data to any cell in your spreadsheet.

Now let’s find out how to add and remove a worksheet!

Adding and Removing Sheets

Adding a worksheet to a workbook happens automatically when you create a new Workbook. The Worksheet will be named “Sheet” by default. If you want, you can set the name of the sheet yourself.

To see how this works, create a new file named creating_sheet_title.py and add the following code:

# creating_sheet_title.py

from openpyxl import Workbook


def create_sheets(path):
    workbook = Workbook()
    sheet = workbook.active
    sheet.title = "Hello"
    sheet2 = workbook.create_sheet(title="World")
    workbook.save(path)


if __name__ == "__main__":
    create_sheets("hello_sheets.xlsx")

Here you create the Workbook and then grab the active Worksheet. You can then set the Worksheet’s title using the title attribute. The following line of code adds a new worksheet to the Workbook by calling create_sheet().

The create_sheet() method takes two parameters: title and index. The title attribute gives a title to the Worksheet. The index tells the Workbook where to insert the Worksheet, from left to right. If you specify zero, your Worksheet gets inserted at the beginning.

If you run this code, your new spreadsheet will look like this:

Creating Multiple Worksheets

Sometimes you will need to delete a worksheet. Perhaps that sheet no longer has valid information, or it was created by accident.

To see how to delete a worksheet, create another new file and name it delete_sheets.py. Then add this code:

# delete_sheets.py

import openpyxl


def create_worksheets(path):
    workbook = openpyxl.Workbook()
    workbook.create_sheet()
    print(workbook.sheetnames)
    # Insert a worksheet
    workbook.create_sheet(index=1, title="Second sheet")
    print(workbook.sheetnames)
    del workbook["Second sheet"]
    print(workbook.sheetnames)
    workbook.save(path)


if __name__ == "__main__":
    create_worksheets("del_sheets.xlsx")

In this example, you create two new sheets. The first Worksheet has no title specified, so it defaults to “Sheet1”. You supply a title to the second sheet, and then you print out all the current worksheet titles.

Next, you use Python’s del keyword to delete the Worksheet’s name from the workbook, which removes the sheet. Then you print out the current worksheet titles again.

Here is the output from running the code:

['Sheet', 'Sheet1']
['Sheet', 'Second sheet', 'Sheet1']
['Sheet', 'Sheet1']

The first Worksheet gets created automatically when you instantiate the Workbook. The Worksheet is named “Sheet”. Then you make “Sheet1”. Lastly, you create “Second sheet”, but you insert it at position 1, which tells the Workbook to shift ‘Sheet1’ to the right by one position.

You can see from the output above how the worksheets are ordered before and after you add and delete the “Second sheet”.

Now let’s learn about inserting and removing rows and columns!

Inserting and Deleting Rows and Columns

The OpenPyXL package provides you with several methods that you can use to insert or delete rows and columns. These methods are a part of the Worksheet object.

You will learn about the following four methods:

  • .insert_rows()
  • .delete_rows()
  • .insert_cols()
  • .delete_cols()

Each of these methods can take these two arguments:

  • idx – The index to insert into (or delete from)
  • amount – The number of rows or columns to add (or delete)

You can use the insert methods to insert rows or columns at the specified index.

Open up a new file and name it insert_demo.py. Then enter this code in your new file:

# insert_demo.py

from openpyxl import Workbook


def inserting_cols_rows(path):
    workbook = Workbook()
    sheet = workbook.active
    sheet["A1"] = "Hello"
    sheet["A2"] = "from"
    sheet["A3"] = "OpenPyXL"
    # insert a column before A
    sheet.insert_cols(idx=1)
    # insert 2 rows starting on the second row
    sheet.insert_rows(idx=2, amount=2)
    workbook.save(path)


if __name__ == "__main__":
    inserting_cols_rows("inserting.xlsx")

Here you create another new Spreadsheet. In this case, you add text to the first three cells in the “A” column. Then you insert one column at index one. That means you inserted a single column before “A”, which causes the cells in column “A” to shift to column “B”.

Next, you insert two new rows starting at index two. This code will insert two rows between the first and second rows.

You can see how this changes things by taking a look at the following screenshot:

Inserting rows and columns

Try changing the indexes or number of rows and columns that you want to insert and see how it works.

You will also need to delete columns and rows from time to time. To do that you will use .delete_rows() and .delete_cols().

Open up a new file and name it delete_demo.py. Then add this code:

# delete_demo.py

from openpyxl import Workbook


def deleting_cols_rows(path):
    workbook = Workbook()
    sheet = workbook.active
    sheet["A1"] = "Hello"
    sheet["B1"] = "from"
    sheet["C1"] = "OpenPyXL"
    sheet["A2"] = "row 2"
    sheet["A3"] = "row 3"
    sheet["A4"] = "row 4"
    # Delete column A
    sheet.delete_cols(idx=1)
    # delete 2 rows starting on the second row
    sheet.delete_rows(idx=2, amount=2)
    workbook.save(path)


if __name__ == "__main__":
    deleting_cols_rows("deleting.xlsx")

In this example, you add text to six different cells. Four of those cells are in column “A”. Then you use delete_cols() to delete column “A”! That means you got rid of four values. Next, you delete two rows, starting at row number two.

When you run this code, your result should look like this:

Deleting Rows and Columns

Try editing the index or amount values to get familiar with deleting rows and columns.

Now you are ready to learn about editing a spreadsheet’s values!

Editing Cell Data

You can use OpenPyXL to change the values in a pre-existing Excel spreadsheet. You can do that by specifying the cell you want to change and then setting it to a new value.

For this example, you will use the inserting.xlsx file you created in the previous section. Now create a new Python file named editing_demo.py. Then add the following code:

# editing_demo.py

from openpyxl import load_workbook


def edit(path, data):
    workbook = load_workbook(filename=path)
    sheet = workbook.active
    for cell in data:
        current_value = sheet[cell].value
        sheet[cell] = data[cell]
        print(f'Changing {cell} from {current_value} to {data[cell]}')
    workbook.save(path)

if __name__ == "__main__":
    data = {"B1": "Hi", "B5": "Python"}
    edit("inserting.xlsx", data)

This code loads up the Excel file that you created in the previous section. It then loops over each value in the data dictionary that you passed to the edit() function. You get the current value for the cell using a key in the dictionary. Then you change that cell’s value to match the value in the dictionary.

To make it more obvious what is going on, you print out the old and new values of the cell.

When you run this code, you will see the following output:

Changing B1 from Hello to Hi
Changing B5 from OpenPyXL to Python

Open up the new version of the inserting.xlsx file, and it should now look like this:

Editing Cells

Here you can see how the cell values have changed to match the one specified in the data dictionary.

Now you can move on and learn how to create merged cells!

Creating Merged Cells

A merged cell is where two or more cells get merged into one. To set a MergedCell’s value, you have to use the top-left-most cell. For example, if you merge “A2:E2”, you would set the value of cell “A2” for the merged cells.

To see how this works in practice, create a file called merged_cells.py and add this code to it:

# merged_cells.py

from openpyxl import Workbook
from openpyxl.styles import Alignment


def create_merged_cells(path, value):
    workbook = Workbook()
    sheet = workbook.active
    sheet.merge_cells("A2:E2")
    top_left_cell = sheet["A2"]
    top_left_cell.alignment = Alignment(horizontal="center",
                                        vertical="center")
    sheet["A2"] = value
    workbook.save(path)


if __name__ == "__main__":
    create_merged_cells("merged.xlsx", "Hello World")

OpenPyXL has many ways to style cells. In this example, you import Alignment from openpyxl.styles. You will learn more about styles and formatting cells in a later chapter.

Here you merge the cells “A2:E2” and set the alignment to the center of the cell. Then you set the value of “A2” to a string that you passed to the create_merged_cells() function.

When you run this example, your new Excel spreadsheet will look like this:

Merged Cells

To get some hands-on experience, change the range of cells you want to merge and try it with and without the alignment set.

Now you are ready to learn about folding columns or rows!

Folding Rows and Columns

Microsoft Excel supports the folding of rows and columns. The term “folding” is also called “hiding” or creating an “outline”. The rows or columns that get folded can be unfolded (or expanded) to make them visible again. You can use this functionality to make a spreadsheet briefer. For example, you might want to only show the sub-totals or the results of equations rather than all of the data at once.

OpenPyXL supports folding too. To see how this works, create a new file named folding.py and enter the following code:

# folding.py

import openpyxl


def folding(path, rows=None, cols=None, hidden=True):
    workbook = openpyxl.Workbook()
    sheet = workbook.active

    if rows:
        begin_row, end_row = rows
        sheet.row_dimensions.group(begin_row, end_row, hidden=hidden)

    if cols:
        begin_col, end_col = cols
        sheet.column_dimensions.group(begin_col, end_col, hidden=hidden)

    workbook.save(path)


if __name__ == "__main__":
    folding("folded.xlsx", rows=(1, 5), cols=("C", "F"))

Your folding() function accepts a tuple of rows or columns or both. You can tell OpenPyXL whether or not you want those rows and columns to be hidden, or folded. In this example, you fold rows 1-5 and columns C-F. To cause the folding to occur, you need to call sheet.row_dimensions.group().

When you run this code, your spreadsheet will look like this:

Folding Cells

You can see in this spreadsheet that some of the rows and columns are folded or hidden. There is a “+” symbol next to row 6 and another “+” symbol above column “G”. If you click on either of those buttons, it will expand the folded rows or columns.

Give this code a try. You can also experiment with different row or column ranges.

Now you are ready to learn how to freeze a pane!

Freezing Panes

Microsoft Excel allows you to freeze panes. What that means is that you can freeze one or more columns or rows. One popular use case is to freeze a row of headers so that the headers are always visible while scrolling through a lot of data.

OpenPyXL provides a freeze_panes attribute on the Worksheet object that you can set. You need to select a cell below and to the right of the columns that you want to freeze. For example, if you want to freeze the first row in your spreadsheet, then you would select cell at “A2” to apply the freeze to that row.

You can see how this works by writing some code. Open up a new file and name it freezing_panes.py. Then enter the following into it:

# freezing_panes.py

from openpyxl import Workbook


def freeze(path, row_to_freeze):
    workbook = Workbook()
    sheet = workbook.active
    sheet.title = "Freeze"
    sheet.freeze_panes = row_to_freeze
    headers = ["Name", "Address", "State", "Zip"]
    sheet["A1"] = headers[0]
    sheet["B1"] = headers[1]
    sheet["C1"] = headers[2]
    sheet["D1"] = headers[3]
    data = [dict(zip(headers, ("Mike", "123 Storm Dr", "IA", "50000"))),
            dict(zip(headers, ("Ted", "555 Tornado Alley", "OK", "90000")))]
    row = 2
    for d in data:
        sheet[f'A{row}'] = d["Name"]
        sheet[f'B{row}'] = d["Address"]
        sheet[f'C{row}'] = d["State"]
        sheet[f'D{row}'] = d["Zip"]
        row += 1
    workbook.save(path)


if __name__ == "__main__":
    freeze("freeze.xlsx", row_to_freeze="A2")

Here you create a new Workbook and set the active sheet’s title to “Freeze”. Then you set the freeze_panes attribute to “A2”. The rest of the code in the function adds a couple of rows of data to the Worksheet.

When you run this code, the spreadsheet that you create will look like this:

Freeze Panes

Try scrolling down through some rows in the spreadsheet. The top row should always remain visible because it has been “frozen”.

Wrapping Up

You can use OpenPyXL not only to create an Excel spreadsheet, but modify a pre-existing one. In this chapter, you learned how to do the following:

  • Create a spreadsheet
  • Write to a spreadsheet
  • Add and remove sheets
  • Insert and delete rows and columns
  • Edit cell data
  • Create merged cells
  • Freeze panes

Give the examples in this chapter a try. Then modify them a bit to see what else you can do on your own.

You all must have worked with Excel at some time in your life and must have felt the need for automating some repetitive or tedious task. Don’t worry in this tutorial we are going to learn about how to work with Excel using Python, or automating Excel using Python. We will be covering this with the help of the Openpyxl module.

Getting Started

Openpyxl is a Python library that provides various methods to interact with Excel Files using Python. It allows operations like reading, writing, arithmetic operations, plotting graphs, etc.

This module does not come in-built with Python. To install this type the below command in the terminal.

pip install openpyxl

Python Excel tutorial openpyxl install

Reading from Spreadsheets

To read an Excel file you have to open the spreadsheet using the load_workbook() method. After that, you can use the active to select the first sheet available and the cell attribute to select the cell by passing the row and column parameter. The value attribute prints the value of the particular cell. See the below example to get a better understanding. 

Note: The first row or column integer is 1, not 0.

Dataset Used: It can be downloaded from here.

python excel readin excel openpyxl

Example:

Python3

import openpyxl 

path = "gfg.xlsx"

wb_obj = openpyxl.load_workbook(path) 

sheet_obj = wb_obj.active 

cell_obj = sheet_obj.cell(row = 1, column = 1

print(cell_obj.value) 

Output:

Name

Reading from Multiple Cells

There can be two ways of reading from multiple cells. 

Method 1: We can get the count of the total rows and columns using the max_row and max_column respectively. We can use these values inside the for loop to get the value of the desired row or column or any cell depending upon the situation. Let’s see how to get the value of the first column and first row.

Example:

Python3

import openpyxl 

path = "gfg.xlsx"

wb_obj = openpyxl.load_workbook(path) 

sheet_obj = wb_obj.active 

row = sheet_obj.max_row

column = sheet_obj.max_column

print("Total Rows:", row)

print("Total Columns:", column)

print("nValue of first column")

for i in range(1, row + 1): 

    cell_obj = sheet_obj.cell(row = i, column = 1

    print(cell_obj.value) 

print("nValue of first row")

for i in range(1, column + 1): 

    cell_obj = sheet_obj.cell(row = 2, column = i) 

    print(cell_obj.value, end = " ")

Output:

Total Rows: 6
Total Columns: 4

Value of first column
Name
Ankit
Rahul
Priya
Nikhil
Nisha

Value of first row
Ankit  B.Tech CSE 4 

Method 2: We can also read from multiple cells using the cell name. This can be seen as the list slicing of Python.

Python3

import openpyxl 

path = "gfg.xlsx"

wb_obj = openpyxl.load_workbook(path) 

sheet_obj = wb_obj.active 

cell_obj = sheet_obj['A1': 'B6']

for cell1, cell2 in cell_obj:

    print(cell1.value, cell2.value)

Output:

Name Course
Ankit  B.Tech
Rahul M.Tech
Priya MBA
Nikhil B.Tech
Nisha B.Tech

Refer to the below article to get detailed information about reading excel files using openpyxl.

  • Reading an excel file using Python openpyxl module

Writing to Spreadsheets

First, let’s create a new spreadsheet, and then we will write some data to the newly created file. An empty spreadsheet can be created using the Workbook() method. Let’s see the below example.

Example:

Python3

from openpyxl import Workbook

workbook = Workbook()

workbook.save(filename="sample.xlsx")

Output:

empty spreadsheet using Python

After creating an empty file, let’s see how to add some data to it using Python. To add data first we need to select the active sheet and then using the cell() method we can select any particular cell by passing the row and column number as its parameter. We can also write using cell names. See the below example for a better understanding.

Example:

Python3

import openpyxl 

wb = openpyxl.Workbook() 

sheet = wb.active 

c1 = sheet.cell(row = 1, column = 1

c1.value = "Hello"

c2 = sheet.cell(row= 1 , column = 2

c2.value = "World"

c3 = sheet['A2'

c3.value = "Welcome"

c4 = sheet['B2'

c4.value = "Everyone"

wb.save("sample.xlsx"

Output:

python excel writing to file

Refer to the below article to get detailed information about writing to excel.

  • Writing to an excel file using openpyxl module

Appending to the Spreadsheet

In the above example, you will see that every time you try to write to a spreadsheet the existing data gets overwritten, and the file is saved as a new file. This happens because the Workbook() method always creates a new workbook file object. To write to an existing workbook you must open the file with the load_workbook() method. We will use the above-created workbook.

Example:

Python3

import openpyxl 

wb = openpyxl.load_workbook("sample.xlsx"

sheet = wb.active 

c = sheet['A3'

c.value = "New Data"

wb.save("sample.xlsx")

Output:

append data excel python

We can also use the append() method to append multiple data at the end of the sheet.

Example:

Python3

import openpyxl 

wb = openpyxl.load_workbook("sample.xlsx"

sheet = wb.active 

data = (

    (1, 2, 3),

    (4, 5, 6)

)

for row in data:

    sheet.append(row)

wb.save('sample.xlsx')

Output:

append data excel python

Arithmetic Operation on Spreadsheet

Arithmetic operations can be performed by typing the formula in a particular cell of the spreadsheet. For example, if we want to find the sum then =Sum() formula of the excel file is used.

Example:

Python3

import openpyxl 

wb = openpyxl.Workbook() 

sheet = wb.active 

sheet['A1'] = 200

sheet['A2'] = 300

sheet['A3'] = 400

sheet['A4'] = 500

sheet['A5'] = 600

sheet['A7'] = '= SUM(A1:A5)'

wb.save("sum.xlsx"

Output:

finding sum excel python

Refer to the below article to get detailed information about the Arithmetic operations on Spreadsheet.

  • Arithmetic operations in excel file using openpyxl

Adjusting Rows and Column

Worksheet objects have row_dimensions and column_dimensions attributes that control row heights and column widths. A sheet’s row_dimensions and column_dimensions are dictionary-like values; row_dimensions contains RowDimension objects and column_dimensions contains ColumnDimension objects. In row_dimensions, one can access one of the objects using the number of the row (in this case, 1 or 2). In column_dimensions, one can access one of the objects using the letter of the column (in this case, A or B).

Example:

Python3

import openpyxl 

wb = openpyxl.Workbook() 

sheet = wb.active 

sheet.cell(row = 1, column = 1).value = ' hello '

sheet.cell(row = 2, column = 2).value = ' everyone '

sheet.row_dimensions[1].height = 70

sheet.column_dimensions['B'].width = 20

wb.save('sample.xlsx'

Output:

adjusting rows and columns excel python

Merging Cells

A rectangular area of cells can be merged into a single cell with the merge_cells() sheet method. The argument to merge_cells() is a single string of the top-left and bottom-right cells of the rectangular area to be merged.

Example:

Python3

import openpyxl 

wb = openpyxl.Workbook() 

sheet = wb.active 

sheet.merge_cells('A2:D4'

sheet.cell(row = 2, column = 1).value = 'Twelve cells join together.'

sheet.merge_cells('C6:D6'

sheet.cell(row = 6, column = 6).value = 'Two merge cells.'

wb.save('sample.xlsx')

Output:

merge cells excel python

Unmerging Cells

To unmerge cells, call the unmerge_cells() sheet method.

Example:

Python3

import openpyxl 

wb = openpyxl.load_workbook('sample.xlsx'

sheet = wb.active 

sheet.unmerge_cells('A2:D4'

sheet.unmerge_cells('C6:D6'

wb.save('sample.xlsx')

Output:

unmerge cells excel python

Setting Font Style

To customize font styles in cells, important, import the Font() function from the openpyxl.styles module.

Example:

Python3

import openpyxl 

from openpyxl.styles import Font 

wb = openpyxl.Workbook() 

sheet = wb.active 

sheet.cell(row = 1, column = 1).value = "GeeksforGeeks"

sheet.cell(row = 1, column = 1).font = Font(size = 24

sheet.cell(row = 2, column = 2).value = "GeeksforGeeks"

sheet.cell(row = 2, column = 2).font = Font(size = 24, italic = True

sheet.cell(row = 3, column = 3).value = "GeeksforGeeks"

sheet.cell(row = 3, column = 3).font = Font(size = 24, bold = True

sheet.cell(row = 4, column = 4).value = "GeeksforGeeks"

sheet.cell(row = 4, column = 4).font = Font(size = 24, name = 'Times New Roman'

wb.save('sample.xlsx'

Output:

setting style excel python

Refer to the below article to get detailed information about adjusting rows and columns.

  • Adjusting rows and columns of an excel file using openpyxl module

Plotting Charts

Charts are composed of at least one series of one or more data points. Series themselves are comprised of references to cell ranges. For plotting the charts on an excel sheet, firstly, create chart objects of specific chart class( i.e BarChart, LineChart, etc.). After creating chart objects, insert data in it, and lastly, add that chart object in the sheet object.

Example 1:

Python3

import openpyxl

from openpyxl.chart import BarChart, Reference

wb = openpyxl.Workbook()

sheet = wb.active

for i in range(10):

    sheet.append([i])

values = Reference(sheet, min_col=1, min_row=1,

                   max_col=1, max_row=10)

chart = BarChart()

chart.add_data(values)

chart.title = " BAR-CHART "

chart.x_axis.title = " X_AXIS "

chart.y_axis.title = " Y_AXIS "

sheet.add_chart(chart, "E2")

wb.save("sample.xlsx")

Output:

create chart excel python

Example 2:

Python3

import openpyxl

from openpyxl.chart import LineChart, Reference

wb = openpyxl.Workbook()

sheet = wb.active

for i in range(10):

    sheet.append([i])

values = Reference(sheet, min_col=1, min_row=1,

                   max_col=1, max_row=10)

chart = LineChart()

chart.add_data(values)

chart.title = " LINE-CHART "

chart.x_axis.title = " X-AXIS "

chart.y_axis.title = " Y-AXIS "

sheet.add_chart(chart, "E2")

wb.save("sample.xlsx")

Output:

create chart excel python 2

Refer to the below articles to get detailed information about plotting in excel using Python.

  • Plotting charts in excel sheet using openpyxl module | Set  1
  • Plotting charts in excel sheet using openpyxl module | Set  2
  • Plotting charts in excel sheet using openpyxl module | Set 3

Adding Images

For the purpose of importing images inside our worksheet, we would be using openpyxl.drawing.image.Image. The method is a wrapper over PIL.Image method found in PIL (pillow) library. Due to which it is necessary for the PIL (pillow) library to be installed in order to use this method.

Image Used:

Example:

Python3

import openpyxl 

from openpyxl.drawing.image import Image

wb = openpyxl.Workbook() 

sheet = wb.active

sheet.append([10, 2010, "Geeks", 4, "life"]) 

img = Image("geek.jpg")

sheet.add_image(img, 'A2'

wb.save('sample.xlsx')

Output:

add image excel python

Refer to the below article to get detailed information about adding images.

  • Openpyxl – Adding Image

Some More Functionality of Excel using Python

  • How to delete one or more rows in excel using Openpyxl?
  • Trigonometric operations in excel file using openpyxl
  • How to copy data from one excel sheet to another
  • How to Automate an Excel Sheet in Python?

Pandas можно использовать для чтения и записи файлов Excel с помощью Python. Это работает по аналогии с другими форматами. В этом материале рассмотрим, как это делается с помощью DataFrame.

Помимо чтения и записи рассмотрим, как записывать несколько DataFrame в Excel-файл, как считывать определенные строки и колонки из таблицы и как задавать имена для одной или нескольких таблиц в файле.

Установка Pandas

Для начала Pandas нужно установить. Проще всего это сделать с помощью pip.

Если у вас Windows, Linux или macOS:

pip install pandas # или pip3

В процессе можно столкнуться с ошибками ModuleNotFoundError или ImportError при попытке запустить этот код. Например:

ModuleNotFoundError: No module named 'openpyxl'

В таком случае нужно установить недостающие модули:

pip install openpyxl xlsxwriter xlrd  # или pip3

Будем хранить информацию, которую нужно записать в файл Excel, в DataFrame. А с помощью встроенной функции to_excel() ее можно будет записать в Excel.

Сначала импортируем модуль pandas. Потом используем словарь для заполнения DataFrame:


import pandas as pd

df = pd.DataFrame({'Name': ['Manchester City', 'Real Madrid', 'Liverpool',
'FC Bayern München', 'FC Barcelona', 'Juventus'],
'League': ['English Premier League (1)', 'Spain Primera Division (1)',
'English Premier League (1)', 'German 1. Bundesliga (1)',
'Spain Primera Division (1)', 'Italian Serie A (1)'],
'TransferBudget': [176000000, 188500000, 90000000,
100000000, 180500000, 105000000]})

Ключи в словаре — это названия колонок. А значения станут строками с информацией.

Теперь можно использовать функцию to_excel() для записи содержимого в файл. Единственный аргумент — это путь к файлу:


df.to_excel('./teams.xlsx')

А вот и созданный файл Excel:

файл Excel в python

Стоит обратить внимание на то, что в этом примере не использовались параметры. Таким образом название листа в файле останется по умолчанию — «Sheet1». В файле может быть и дополнительная колонка с числами. Эти числа представляют собой индексы, которые взяты напрямую из DataFrame.

Поменять название листа можно, добавив параметр sheet_name в вызов to_excel():


df.to_excel('./teams.xlsx', sheet_name='Budgets', index=False)

Также можно добавили параметр index со значением False, чтобы избавиться от колонки с индексами. Теперь файл Excel будет выглядеть следующим образом:

Чтение и запись файлов Excel (XLSX) в Python

Запись нескольких DataFrame в файл Excel

Также есть возможность записать несколько DataFrame в файл Excel. Для этого можно указать отдельный лист для каждого объекта:


salaries1 = pd.DataFrame({'Name': ['L. Messi', 'Cristiano Ronaldo', 'J. Oblak'],
'Salary': [560000, 220000, 125000]})

salaries2 = pd.DataFrame({'Name': ['K. De Bruyne', 'Neymar Jr', 'R. Lewandowski'],
'Salary': [370000, 270000, 240000]})

salaries3 = pd.DataFrame({'Name': ['Alisson', 'M. ter Stegen', 'M. Salah'],
'Salary': [160000, 260000, 250000]})

salary_sheets = {'Group1': salaries1, 'Group2': salaries2, 'Group3': salaries3}
writer = pd.ExcelWriter('./salaries.xlsx', engine='xlsxwriter')

for sheet_name in salary_sheets.keys():
salary_sheets[sheet_name].to_excel(writer, sheet_name=sheet_name, index=False)

writer.save()

Здесь создаются 3 разных DataFrame с разными названиями, которые включают имена сотрудников, а также размер их зарплаты. Каждый объект заполняется соответствующим словарем.

Объединим все три в переменной salary_sheets, где каждый ключ будет названием листа, а значение — объектом DataFrame.

Дальше используем движок xlsxwriter для создания объекта writer. Он и передается функции to_excel().

Перед записью пройдемся по ключам salary_sheets и для каждого ключа запишем содержимое в лист с соответствующим именем. Вот сгенерированный файл:

Чтение и запись файлов Excel (XLSX) в Python

Можно увидеть, что в этом файле Excel есть три листа: Group1, Group2 и Group3. Каждый из этих листов содержит имена сотрудников и их зарплаты в соответствии с данными в трех DataFrame из кода.

Параметр движка в функции to_excel() используется для определения модуля, который задействуется библиотекой Pandas для создания файла Excel. В этом случае использовался xslswriter, который нужен для работы с классом ExcelWriter. Разные движка можно определять в соответствии с их функциями.

В зависимости от установленных в системе модулей Python другими параметрами для движка могут быть openpyxl (для xlsx или xlsm) и xlwt (для xls). Подробности о модуле xlswriter можно найти в официальной документации.

Наконец, в коде была строка writer.save(), которая нужна для сохранения файла на диске.

Чтение файлов Excel с python

По аналогии с записью объектов DataFrame в файл Excel, эти файлы можно и читать, сохраняя данные в объект DataFrame. Для этого достаточно воспользоваться функцией read_excel():


top_players = pd.read_excel('./top_players.xlsx')
top_players.head()

Содержимое финального объекта можно посмотреть с помощью функции head().

Примечание:

Этот способ самый простой, но он и способен прочесть лишь содержимое первого листа.

Посмотрим на вывод функции head():

Name Age Overall Potential Positions Club
0 L. Messi 33 93 93 RW,ST,CF FC Barcelona
1 Cristiano Ronaldo 35 92 92 ST,LW Juventus
2 J. Oblak 27 91 93 GK Atlético Madrid
3 K. De Bruyne 29 91 91 CAM,CM Manchester City
4 Neymar Jr 28 91 91 LW,CAM Paris Saint-Germain

Pandas присваивает метку строки или числовой индекс объекту DataFrame по умолчанию при использовании функции read_excel().

Это поведение можно переписать, передав одну из колонок из файла в качестве параметра index_col:


top_players = pd.read_excel('./top_players.xlsx', index_col='Name')
top_players.head()

Результат будет следующим:

Name Age Overall Potential Positions Club
L. Messi 33 93 93 RW,ST,CF FC Barcelona
Cristiano Ronaldo 35 92 92 ST,LW Juventus
J. Oblak 27 91 93 GK Atlético Madrid
K. De Bruyne 29 91 91 CAM,CM Manchester City
Neymar Jr 28 91 91 LW,CAM Paris Saint-Germain

В этом примере индекс по умолчанию был заменен на колонку «Name» из файла. Однако этот способ стоит использовать только при наличии колонки со значениями, которые могут стать заменой для индексов.

Чтение определенных колонок из файла Excel

Иногда удобно прочитать содержимое файла целиком, но бывают случаи, когда требуется получить доступ к определенному элементу. Например, нужно считать значение элемента и присвоить его полю объекта.

Это делается с помощью функции read_excel() и параметра usecols. Например, можно ограничить функцию, чтобы она читала только определенные колонки. Добавим параметр, чтобы он читал колонки, которые соответствуют значениям «Name», «Overall» и «Potential».

Для этого укажем числовой индекс каждой колонки:


cols = [0, 2, 3]

top_players = pd.read_excel('./top_players.xlsx', usecols=cols)
top_players.head()

Вот что выдаст этот код:

Name Overall Potential
0 L. Messi 93 93
1 Cristiano Ronaldo 92 92
2 J. Oblak 91 93
3 K. De Bruyne 91 91
4 Neymar Jr 91 91

Таким образом возвращаются лишь колонки из списка cols.

В DataFrame много встроенных возможностей. Легко изменять, добавлять и агрегировать данные. Даже можно строить сводные таблицы. И все это сохраняется в Excel одной строкой кода.

Рекомендую изучить DataFrame в моих уроках по Pandas.

Выводы

В этом материале были рассмотрены функции read_excel() и to_excel() из библиотеки Pandas. С их помощью можно считывать данные из файлов Excel и выполнять запись в них. С помощью различных параметров есть возможность менять поведение функций, создавая нужные файлы, не просто копируя содержимое из объекта DataFrame.

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