How to Compare Two Word Documents Using Python

Whether you are grading papers, conducting research, or managing important documents at work, there is often a need to compare two Word documents for changes or similarities.

This may seem an arduous task, especially with lengthy documents. Fortunately, Python offers efficient solutions that can automate this task. This tutorial will guide you on how to use Python to compare two Word documents effectively and efficiently.

Step 1: Set Up Your Python Environment

Initially, you must ensure you have installed Python on your machine. For this tutorial, we will use Python 3.7. In addition to Python, we will use a library called docx. To install this library, run the following command in your console:

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pip install python-docx

Step 2: Creating Basic Python Script

Create a new Python file and name it as you wish. In this tutorial, we’ll name it document_comparison.py.

Step 3: Importing the Required Libraries

In the Python file, we first import the necessary libraries. python-docx for reading the Word documents and difflib for comparing the documents:

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import difflib
from docx import Document

Step 4: Reading the Word Documents

We need to read the Word documents that we wish to compare. For this tutorial, we will read two Word documents named doc1.docx and doc2.docx :

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document1 = Document("doc1.docx")
document2 = Document("doc2.docx")

doc1.docx

This is the content of document 1.
It contains some text for comparison.
Here are some differences that will be highlighted.

doc2.docx

This is the content of document 2.
It contains some text for comparison.
Here are some changes that have been made.

Step 5: Comparing the Documents

With the documents read, now we compare them using the difflib library:

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diff = difflib.ndiff(text1.splitlines(), text2.splitlines())
delta = '\n'.join(x[2:] for x in diff if x.startswith('- '))
 
print(delta)

We have now seen how to write a Python program to compare two Word documents. However, it’s important to note that this is a simple comparison script. It will output the lines that are in ‘document1’ but not in ‘document2’.

Full code:

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import difflib
from docx import Document
 
document1 = Document("doc1.docx")
document2 = Document("doc2.docx")
 
# Extract text from the first document
text1 = "\n".join([para.text for para in document1.paragraphs])
 
# Extract text from the second document
text2 = "\n".join([para.text for para in document2.paragraphs])
 
# Compare the text content of the two documents
diff = difflib.ndiff(text1.splitlines(), text2.splitlines())
delta = '\n'.join(x[2:] for x in diff if x.startswith('- '))
 
print(delta)
 
This is the content of document 1.
Here are some differences that will be highlighted.

Conclusion

Python provides a simple yet efficient way to compare Word documents. All you need is a basic understanding of Python and the python-docx library. The difflib library also facilitates elegant and readable comparisons.

However, bear in mind that this tutorial presents a straightforward approach to comparing Word documents.

For complex documents, you may require more advanced methods, including handling format changes and dealing with inserted images or tables.