The fastest way to see what changed between two Word files

Word has a built-in comparison tool that shows you exactly what changed between two versions of a document — additions, deletions, formatting changes, and moved text all highlighted in different colors. Open both documents, go to the Review tab, click Compare, and select the two files you want to check. Word creates a new document showing every difference marked up, so you can see at a glance whether someone added a paragraph, deleted a sentence, or changed a number.

This works best when you're comparing a draft against a final version, checking edits from a colleague, or tracking changes across multiple revisions. The comparison document stays separate from your originals, so you can review it without altering either source file.

Key Takeaways

  • Word's Compare feature creates a new marked-up document showing every change between two files, with additions in one color and deletions in another.
  • You access Compare through the Review tab, and it works on any two Word documents regardless of how different they are.
  • The comparison document is read-only by default and shows changes in the margins, so you can review without accidentally editing.
  • If both documents used Track Changes while being edited, you can combine them instead of comparing, which preserves each person's edits separately.

Using Word's Compare feature for any two documents

Open Word and load whichever document you want to use as your starting point — it doesn't matter which one you open first. Click the Review tab at the top of the ribbon. In the Compare group (toward the right side of the ribbon), click Compare, then select Compare again from the dropdown menu.

A dialog box opens asking you to pick the original document and the revised document. Click the folder icon next to "Original document" and navigate to the first file. Then click the folder icon next to "Revised document" and pick the second file. Click OK. Word creates a new document that shows both versions side by side, with the original on the left and the revised version on the right, and all changes marked in the center panel.

The new comparison document opens in a special view. Deletions appear in red with strikethrough, additions appear in blue and underlined, and moved text shows in green. The left and right panels stay synchronized — when you click a change in the center, both side panels jump to that location so you can see the context.

Understanding what the comparison shows you

The comparison document displays three panels by default: the original document on the left, the revised document on the right, and a summary in the middle showing only the changes. Each change is numbered and color-coded. Red strikethrough text means something was removed. Blue underlined text means something was added. If text moved from one place to another, it shows in green.

At the top of the middle panel, you'll see a list of all changes. Click any change in that list and Word highlights it in all three panels so you can see exactly where it occurred and what surrounded it. This is especially useful in long documents where a single-word change might be hard to spot otherwise.

If the documents are very different — for example, if one is a completely rewritten version — the comparison still works, but you may see large blocks marked as changed rather than individual words. This is normal and just means Word couldn't match up the text precisely enough to show word-by-word differences.

Combining documents when both used Track Changes

If you're working with colleagues who each edited a document and turned on Track Changes, comparing them creates a mess because you'll see all their individual edits plus all the differences between versions. Instead, use Combine. This merges both sets of tracked changes into one document, keeping each person's edits separate and labeled with their name.

Go to Review, click Compare, and select Combine from the dropdown. Pick the first document as the original and the second as the revised document. Word creates a new file showing all tracked changes from both documents, with each person's edits marked with their username. You can then accept or reject changes one by one, or review them all at once before deciding.

Saving and sharing the comparison results

The comparison document Word creates is a new file that exists only on your computer until you save it. You can save it with a new name so you keep the original files unchanged. Go to File, click Save As, give it a name like "Comparison_Draft_vs_Final", and choose where to store it.

The comparison document is read-only by default, which prevents accidental edits. If you need to make changes to it, click Edit Document at the top of the screen. You can then edit, delete changes, or accept specific edits. Most of the time, though, you'll just review it and then return to one of the original documents to make any changes you decide on.

If you need to share the comparison with someone else, send them the comparison file. They can open it in Word and see all the marked differences without needing the original files, though having the originals makes it easier to understand context.

When comparison doesn't work the way you expect

If Word shows huge blocks of text as changed when you expected to see small differences, the documents may have different formatting, different line breaks, or different paragraph structures. This doesn't mean the comparison is wrong — it just means Word couldn't match up the text precisely. You can still see what changed by reading the marked-up text, but you may need to look more carefully.

If one document is in a different format — for example, one is a .docx file and the other is a .doc file — Word converts them both to the same format before comparing, so this usually isn't a problem. However, if one document is a PDF or another non-Word format, you'll need to convert it to a Word document first.

If the comparison document shows changes you didn't expect, check whether Track Changes was turned on in either of the original documents. If it was, those tracked changes will show up in the comparison even if you haven't accepted or rejected them yet. You may want to accept or reject all tracked changes in the originals before comparing them.

Alternatives if you prefer a different approach

If you don't like the side-by-side view, you can open both documents in separate windows and arrange them on your screen manually. Click View, then select Arrange All to split your screen between the two documents. You can then scroll through each one independently and spot differences yourself. This takes longer but gives you more control over what you're looking at.

Another option is to use Track Changes in one document while you manually edit it against the other. Open the revised document, turn on Track Changes (Review tab, Track Changes), and then make edits as you compare it to the original. This creates a record of what you changed, which is useful if you need to explain your edits later.

Some people prefer to print both documents and mark them up by hand, especially for shorter files or when they want to annotate their thinking. This is slower but can help you focus on the content rather than getting distracted by the software.

Frequently Asked Questions

Can I compare more than two documents at once?

No, Word's Compare feature only works on two documents at a time. If you need to compare three or more versions, compare the first two, then compare the result against the third document. This gets complicated quickly, so for multiple versions, consider using Track Changes in each document instead and reviewing them one at a time.

Does comparing documents change the originals?

No. The Compare feature creates a new document and leaves both originals untouched. You can review the comparison, close it without saving, and your original files remain exactly as they were.

What if the documents have different page layouts or margins?

Word compares the text content, not the formatting or layout. Differences in margins, fonts, or page breaks won't show up as changes in the comparison. If you need to see formatting differences, you'll have to check those manually by opening both documents side by side.

Can I undo a comparison?

Yes. The comparison document is separate from your originals, so you can close it without saving and it disappears. Your original documents are unaffected. If you saved the comparison document, you can delete that file and you're back where you started.

How do I accept or reject changes in the comparison document?

Open the comparison document, click Review, and use Accept or Reject in the Changes group. You can go through changes one at a time or accept all changes at once. However, most people review the comparison in the read-only view and then go back to one of the original documents to make changes manually, rather than editing the comparison document itself.