Compare Two Files in Word: Step-by-Step Guide

To compare two files in Microsoft Word, open Word and choose Review > Compare > Compare on Windows, then select the original and revised documents and choose OK. Word creates a separate comparison document that marks differences without changing either source file. On Mac, use Review > Compare > Compare Documents.

What You’ll Need

Two versions of a document: Decide which one is the original and which is the revised version. Word uses those roles to identify the direction of changes in the comparison.
Microsoft Word desktop: The instructions below are for Word for Microsoft 365 on Windows. The Mac path is noted where it differs. If you are using Word in a browser and cannot find Compare, open the files in the desktop app.
Access to both files: Save them somewhere you can browse to, such as your computer or an accessible cloud folder. Using copies is a sensible precaution if the files are important.
A few minutes to review the result: A comparison is a useful guide, not a substitute for checking that the changes Word identifies are meaningful.

Step-by-Step

Prepare the two documents. Close any duplicate or outdated versions so you can identify the right files easily. If possible, keep both documents in the same folder and use clear names such as Proposal-original.docx and Proposal-revised.docx. You do not have to open both files first; Word can locate them from the Compare window. Check that each one opens normally before starting.
Open Word and start Compare. In Word for Microsoft 365 on Windows, open a blank document or any document, select the Review tab, and choose Compare in the Compare group. Select Compare from the menu. In some ribbon layouts, the command may be represented by a small drop-down arrow. On a Mac, open the Review tab and choose Compare > Compare Documents. If the command is not visible, maximize the window or look for it in a collapsed ribbon group.
Choose the original file. In the Compare Documents dialog, use the file picker beside Original document to locate and select the earlier version. Confirm the document name shown in the field. The original is the baseline Word uses to work out what was added, removed, or changed in the other copy.
Choose the revised file. Use the picker beside Revised document to select the later version. Check the filename carefully, particularly if the two versions have similar names. If you accidentally put the newer file in the Original field, the comparison may still run, but additions and deletions will appear in the opposite direction from what you expect.
Set the comparison label. The dialog includes a field for labeling changes. Enter a name or initials that will help you recognize whose changes are being shown, such as “Editor” or “Review copy.” This label identifies the comparison changes in the resulting document; it does not alter the names of the source files.
Choose what Word should compare. Select More or expand the additional comparison settings if you need to control the detail. Word can compare text and, depending on the version and options displayed, items such as formatting, comments, tables, headers and footers, footnotes, or text boxes. For a routine revision, the default options are usually a good starting point. Turn off formatting comparison if you only care about wording and do not want font or layout differences to add visual noise. The available options can vary slightly between Word versions.
Select where to show the results. In Show changes in, choose New document to create a separate comparison copy. This is usually the safest and clearest choice because it leaves the original and revised files untouched. If your dialog offers a choice to display changes at the character or word level, choose character-level detail for small edits or word-level detail for easier reading of longer passages.
Run the comparison. Select OK. Word processes the two files and opens the comparison result. Larger documents or files with extensive formatting may take longer. Do not close Word while it is working; if it appears stuck, give it a moment, then follow the troubleshooting steps below.
Review the comparison document. The result uses revision-style markup to show insertions, deletions, and other selected differences. Depending on your view settings, changes may appear in the document itself, in balloons, or in a reviewing pane. Select a marked change to inspect it, and use the Review tab’s navigation controls to move through changes. If the markup is hard to read, open Review > Tracking options such as Display for Review or Show Markup and adjust the view. These display settings affect what you see, not the comparison’s source files.
Save the result separately. Use File > Save As and give the comparison a distinct name, such as Proposal-comparison.docx. Save it in a location where you can find it. The comparison document is a new working file; saving it does not replace either selected source unless you deliberately choose to save over one of them. Keep the two original versions until you have finished reviewing and sharing the result.

Common Mistakes

Reversing the original and revised files: This is the most confusing setup error. Word can still show differences, but changes may look like deletions when you expected additions. Check the dates and filenames in both fields before selecting OK.
Comparing unrelated copies: If the files are not genuinely different versions of the same document, Word may mark large sections as changed. Make sure the documents share the same starting content and that you have selected the intended pair.
Assuming the comparison overwrites a file: Word normally creates a result document when you choose that output option. The comparison is not automatically merged into the revised file. Save the result separately and make any final decisions yourself.
Ignoring formatting differences: A changed font, paragraph spacing, or page layout can produce a busy result even when the wording is unchanged. Turn off formatting comparison when it is not relevant, or leave it on when presentation changes matter.
Treating every mark as a meaningful edit: Differences in spaces, line breaks, fields, or document formatting can create markup that is technically accurate but not important to your review. Inspect the surrounding text before deciding what a change means.

Tips

Use filenames that explain version order. Names that include “before,” “after,” or a date make it easier to assign the correct roles than names such as “final” and “final-new.”
Start with a clean comparison. If the document is crowded with layout marks, run Compare again with only the categories you need selected. You can make a new comparison without altering the source documents.
Keep the result and the sources together. Store the comparison file alongside both versions, or use a folder structure that makes their relationship clear. That helps another reviewer verify where a change came from.
Use Compare rather than relying only on Track Changes. Track Changes shows edits recorded while someone worked in a document. Compare can identify differences between two saved files even if Track Changes was not enabled during editing.
Check the review display before sharing. A document can contain all its comparison markup but display it in a way that is difficult for another person to see. Choose a suitable markup view, then save and reopen the result to confirm it is readable.

Troubleshooting

Compare is missing from the ribbon: Confirm that you are using the Word desktop app, not a limited browser view. In Word for Windows, look under Review > Compare; on Mac, look under Review > Compare. Maximize Word or expand the ribbon if groups are collapsed. If necessary, open the document in the desktop app from Word for the web.
Word says a file cannot be opened: Browse to the file again and check that it still exists, that you have permission to access it, and that it opens in Word on its own. If it is in a shared or cloud folder, wait for syncing to finish or save an accessible copy locally and retry. If the file is damaged, try opening it separately and saving a fresh copy before comparing.
The result shows too many changes: Verify that you selected the correct two versions and that one is not based on a substantially different document. If the files are the right pair, run Compare again and disable categories such as formatting that you do not need. You can also choose word-level rather than character-level display, if available, to make text edits easier to scan.
There are no visible changes: Check the selected filenames and confirm the files actually differ. Then inspect the review display: markup may be hidden by the current view or Show Markup settings. Choose a view that displays revisions and ensure the relevant markup categories are enabled. If the documents differ only in a category excluded from comparison, include that category and run Compare again.
The comparison is difficult to read or Word stops responding: Close other large documents and try again with fresh copies. If the source files contain many comments, embedded objects, or complex layouts, save working copies as current Word documents and compare those. For a large file, wait before clicking again; repeatedly starting the command can make it harder to tell whether Word is still processing.

Frequently Asked Questions

Does comparing two files change either original?
Not when you choose New document for the comparison output. Word makes a separate result. Save that result under a new name and avoid choosing an option that places changes into a source document if you want to preserve both versions.

Can I compare documents if Track Changes was off?
Yes. Compare checks the contents of the two selected files and identifies differences between them. It does not require that editing history or Track Changes was recorded when the changes were made.

Can Word compare two PDFs?
Word’s Compare command is intended for Word documents. If you have PDFs, first open or convert them to editable Word documents, then check the converted text and layout for accuracy before comparing. PDF conversion can change formatting, so do not assume every resulting difference reflects an intentional edit.

Can I compare files in Word for the web?
If Compare is not available in your browser version, open the files in Word for Microsoft 365 on Windows or Mac and use the desktop Review tab. Browser features can differ by account and rollout, so the desktop app is the dependable route for these steps.

How do I accept or reject changes in the comparison?
Select a marked change and use the Review tab’s Accept or Reject controls, or use the navigation options to move through changes. Do this in the saved comparison copy, not in either source, unless you deliberately intend to edit that source.

Can I compare more than two files at once?
The Compare command compares a pair of documents at a time. To follow a series of revisions, compare the first and second versions, then compare the next pair separately. Give each result a clear filename so you can distinguish the comparison stages.

Try it: the Date Difference Calculator: days, months, years and weekdays between two dates, with the DATEDIF formulas.

More in How-to basics

Sources: Function behaviour and menu paths: Microsoft Support documentation for Excel. Method & sources

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