How to Compare Two Documents in Word and Spot Every Change

A client sends back your proposal "with a few tweaks", but forgot to switch on tracking. Or you've got two drafts called final and final-v2 and no idea which one has the right wording. Reading them side by side is slow and you'll miss things. Word's Compare tool does it for you and marks every difference.

Here's how it works on Windows and Mac, how Compare differs from Combine, and how to read the result without getting lost in coloured text.

What Word's Compare feature produces

Compare never edits your files. According to Microsoft, Word builds a new third document from the two you pick. Differences from the revised file show up as tracked changes, so you can step through them and accept or reject each one, and the source files stay exactly as they were.

That makes it safe to run on anything, including signed-off contracts, because you're only ever working on a fresh copy.

Comparing two Word documents on Windows

1. Open Word. Microsoft's help suggests opening both files you plan to compare.
2. Go to the Review tab and, in the Compare group, select Compare.
3. Choose Compare two versions of a document (legal blackline).
4. Under Original document, browse to the earlier or base file.
5. Under Revised document, pick the newer file.
6. Select OK.

If either file already contains tracked changes, Microsoft says a message box appears. Select Yes to accept those changes and carry on with the comparison.

Comparison settings for Word documents

Before you select OK, you can fine-tune what Word looks at. Microsoft lists options to include or ignore comments, formatting and text changes. Under Show changes, you can choose to see differences at character level or word level. Word level is usually easier to read, while character level catches a single changed digit or letter.

By default, results open in a new document. Under Show changes in, you can send them into the original or revised file instead, but Microsoft points out that this changes that document. I'd leave it on new document unless you've got a good reason.

Comparing two documents in Word for Mac

1. Open one of the two versions.
2. On the Review tab, choose Compare, then Compare Documents.
3. In the Original document list, choose the original.
4. In the Revised document list, browse to the other version and select OK.

Microsoft says Word creates a new copy based on the original, with revision marks showing what changed, and leaves the original untouched. Menus vary by version, so if you don't see Compare, look under the Tools menu and Track Changes.

Compare versus Combine in Word

These sit in the same menu and sound alike, but they solve different problems.

Tool	Use it when	What you get
Compare	You want to see what changed between two versions	A new document showing the differences as tracked changes
Combine	Several people edited separate copies and you want all their edits in one file	A new document holding everyone's edits, labelled by reviewer

Microsoft specifically advises against the legal blackline Compare option for pulling together edits from several reviewers. Use Combine for that instead.

Merging several reviewers' copies with Combine in Word

1. Go to Review, Compare, Combine.
2. Under Original document, choose the copy you sent out, the one without changes.
3. Under Revised document, choose a reviewer's copy.
4. In Label unmarked changes with, type the reviewer's name so you know whose edits are whose.
5. Select More, choose New document under Show changes in, and select OK.

For a third or fourth reviewer, save the combined file, run Combine again with that file as the original and the next copy as revised, and this time choose Original document under Show changes in. Microsoft also notes that sharing one file on OneDrive and inviting people to edit it avoids the whole merging process, which I'd recommend for regular team documents.

Reading a Word comparison without getting overwhelmed

The results window can look busy, with side panes showing the source files. If it's too much, Microsoft's tip is to go to Review, Compare, Show Source Documents and choose Hide Source Documents. You'll then see red vertical lines in the margin marking where text has changed.

• Work from the top and use the review tools to accept or reject each change.
• Leave formatting changes until last, since they're rarely the bit that matters.
• Save the comparison under a clear name, such as the client's name followed by compared, so you can find it later.

Comparing Word documents for freelance and client work

For anyone who writes for clients, Compare is a quiet lifesaver. It shows exactly what an editor changed in your copy, which helps you learn their style fast and protects you if wording's disputed later. If you're building up client work, my guide to landing your first freelance content writing job covers how to handle feedback rounds. And if you're the one checking a writer's drafts, my article on whether AI writing counts as plagiarism is a helpful companion when you're reviewing copy.

Frequently asked questions

Does comparing documents in Word change my original files?

No. Microsoft says Word creates a new third document and the source files aren't changed, unless you choose to show changes in the original or revised document.

What's the difference between Compare and Combine in Word?

Compare shows what changed between two versions. Combine merges edits from several reviewers' copies into one document, and Microsoft recommends it for multiple reviewers.

Can Word compare documents that already have tracked changes?

Yes. Microsoft says a message box appears, and selecting Yes accepts those existing changes so the comparison can continue.

How do I hide the extra panes after comparing in Word?

Go to Review, Compare, Show Source Documents and choose Hide Source Documents.

Which file should be the original when comparing in Word?

Choose the earlier or base version as the Original document and the newer one as the Revised document. The revised file's differences then appear as tracked changes, which makes the review read in the right direction.

Can I compare documents in Word for Mac?

Yes. On the Review tab, choose Compare, then Compare Documents, pick the original and revised files and select OK.