How to mark the differences after comparing Word documents

Key points of this article

After the comparison results come out, check the revision list one by one from the first item, and then add comments on important changes. Do not read through it directly based on your impressions.
The direction of comparison is critical: the original version and the revised version are placed upside down, insertions and deletions will be reversed, and readers will misunderstand the direction of changes.
The comparison function marks changes. The unmarked text is the similarities between the two articles. You can hide the marks and sort them out.
Scanned documents cannot be directly compared. First determine whether the text can be selected. If it can be selected, compare it. Otherwise, OCR recognition is required first.
After finishing, check whether there are too many format revisions, whether tables and pictures are missing labels, and spot-check important figures and terms.

Putting two contracts, two versions of papers or two draft reports together, it is time-consuming to compare them word for word. Many people have used the document comparison function, but the result is a screen full of revision marks. They don't know where to start, and they can't tell which ones are substantive changes and which ones are just font or spacing changes.

This article talks about the step after the comparison is completed: how to locate the differences one by one, mark them clearly with annotations and colors, and sort out the parts that have not changed (that is, the similarities between the two articles). After reading it, you can check every change in a fixed order, and you can clearly explain what has been changed when handing it over to others.

After comparing Word documents, how to find and mark the differences? One sentence conclusion

First use the revision marks generated by comparison to locate them one by one, and then use comments to fix the important changes; the similarities will be sorted based on the "unmarked parts".

your situation	Recommended practices	reason
Two Word documents, just want to see what has been changed	Starting from the first item in the revised list, refer to the original text one by one.	It is easy to miss insertions and deletions when looking in sequence
The differences need to be confirmed by others	Keep revision marks and comment on key changes	The other party can see the changed location and the basis for your judgment.
Want to get the same content from two articles	Hide revision marks and copy unmarked paragraphs to a new document	The same parts will not appear in the markup originally
Only care about numbers, amounts or terms	First use the search function to search for keywords, and then compare it with revisions	Small numbers in long paragraphs are easily overlooked
File is a PDF or scan	Use PDF comparison when text can be selected; do OCR on scanned documents first	Relying on recognizable text

Before you start: Confirm these points first

Confirm the order of versions. When comparing, be clear which copy is the original version and which copy is the revised version. If the direction is reversed, insertion and deletion will be interchanged, and readers will think that the author has deleted content that should be retained.
Confirm file format. When both copies are .docx, it is easier to use the document comparison function of the office software directly. If you only have PDF, you need to use PDF to compare, or convert it to a Word document first and then compare. The markup styles of the two methods are different.
Confirm whether it is a scanned copy. The text in the scan is an image and cannot be compared directly. The judgment method is very simple: open the PDF and use the mouse to drag and select a piece of text. If you cannot select it, it is a scanned copy.
Decide whether to pay attention to format changes. If the revised version only changes the font, line spacing or margins, the comparison result will show a large number of formatting revisions, which will interfere with reading. First, think clearly whether the content or layout differences you want to look at this time are differences.
Keep the original. Comparison results generally generate new documents, and the original files should not be overwritten directly. Save as a new name to return to the original version at any time.

Steps to highlight differences point by point in a Word document

Open the two documents, identify the original version and the revised version, and name them respectively, such as "Contract_v1" and "Contract_v2" to avoid confusion.
Find the document comparison function in the office software, select the original version and the revised version in sequence, and confirm that the two files are being compared, not the currently unsaved edits.
Generate comparison results. The results will appear in the form of a new document. New content is usually underlined and colored, and deleted content is usually strikethrough.
Open the revision list or the revision pane on the side and browse item by item starting from the first item. Every time you read an article, go back to the text and check the context to make sure it is indeed a substantial change.
Select the text for important changes and add comments to indicate the reasons for the changes or issues that require confirmation from the other party. Annotations tell a better "why" than color alone.
If you need to distinguish the types of changes, you can adjust the display mode in the revision settings so that insertion, deletion and formatting revisions look different; if the default display is clear enough, keep the default.
Save it as a new file, and mark the file name with "difference mark", such as "Contract_Difference Mark_Date", so that it can be sent to others or archived later.

Find the similarities between two articles

The compare function marks changes, so the unmarked text is what is common to both articles. The problem is that these same contents are scattered throughout the text, making it difficult to read them individually. There are three common organizing methods:

Hide revision marks, only view the final text. In revision display settings, switch to no markings; what reads is a clean comparison result, with the same paragraph displayed like other content, allowing you to read along.
Copy unmarked paragraphs section by paragraph. Copy the same confirmation paragraphs into a new document, rearrange them by chapter, and form a draft of 'common content.' This method is suitable for quotation or summarization.
Use highlighting to distinguish identical paragraphs. Add a background color to the same paragraph in the original text, and keep the revision mark where the changes are made. The two types of visual information are separate, making them less likely to be mixed together during reading.

Note that if a paragraph is moved, the comparison feature usually displays it as "Delete" plus "Insert," making it look like two different paragraphs. In such cases, you should judge whether the text is the same based on the content of the text.

📊 Core Comparison

Method	Suitable scenarios	Main limitations
Document comparison feature	Two .docx need to quickly generate the marking results	Markings may be incomplete when paragraphs move or table structure changes
Manually compare each paragraph	Files are short or have complex layouts that require word-for-word confirmation	Time-consuming and long documents can easily cause fatigue and miss out
Modify directly in revision mode	One party submits modification suggestions on the other party's document	Both parties had to work on the same document, making it impossible to reproduce two original versions

If the file is a PDF: Compare and annotate in OmniDoc

If both documents are PDFs, you can use the PDF editor in the OmniDoc desktop client, which supports comparing two PDFs. If it's a scanned version, OCR should first recognize the text before comparison; otherwise, the result will be missing the text content. After comparison, you can edit paragraph text, add signatures, or fill out forms in the PDF editor. You can also export the content to Word or Excel, and then use the above methods to add annotations. Download link see download.omnidoc.top.

If you're more used to handling Word documents on web pages, you can use app.unidoc.top's web editor, which supports editing and saving in Word-compatible formats. Operations in the editor still require manual verification, especially for text obtained by OCR or machine translation, where important numbers, dates, and terms must be cross-checked against the original text item by item.

After completion, check each item one by one

After receiving the comparison results or marking documents, check them according to the checklist below:

Inspection items	How to see it	What should you do if there's a problem?
Number of changes	The number of revised items on the list roughly matches your expectations	If the format revisions far exceed the content changes, disable format comparison and regenerate the content
Direction of changes	What should be deleted should be old content, and what should be inserted should be new content	If the direction is reversed, swap the original and revised versions and compare them again
Tables and images	Whether rows and columns in the table or image additions or removals are marked	Such content labeling may be incomplete and requires manual comparison
Headers, footers, and footnotes	Is there a corresponding revision?	For items not listed in the comparison results, open two separate files to view
Numbers, dates, and terms	Spot check with the original text to confirm nothing was missed	If any omissions are found, add annotations and confirm with the other party

❓ Frequently Asked Questions (FAQ)

1. Should the formatting revisions in the comparison results be kept?

If it's just to see content differences, you can hide format revisions in the display settings to avoid interference with judgment. If you want to explain layout adjustments to others, keep them.

2. If the paragraph order is reversed, what happens to the comparison?

It usually appears as one segment deleted and another inserted, rather than being "moved." When reading, judge whether they are the same paragraph based on the text.

3. Why only look at the same paragraphs and not the changes?

Hide revision marks and read the final text. If you need to save them separately, copy the same paragraph into the new document for organization.

4. What should you look for when choosing a free online comparison tool?

Check file size limits, whether the result has a watermark, whether the upload file saves and deletes instructions, and whether the layout and tables can be retained. For contracts or unpublished manuscripts, prioritize methods that can be handled locally.

📝 Summary

The difficulty in comparing Word documents is not generating results, but understanding them. By checking each item in the revision list, annotating important changes, hiding marks, and organizing identical paragraphs, and then checking the checklist again, you can clearly explain the differences and similarities between the two versions.

Open OmniDoc to edit and export documents online