How to Redline in Word (and Make a Clean Redline)

By EJ Archuleta, Licensed attorney · Updated 2026-10-12

To redline in Word, turn on Track Changes (Review tab) before you edit, so Word marks every insertion and deletion as you type. If the edits are already made, use Compare (Review tab → Compare) to build a redline from two finished versions. To make the redline clean, normalize both files first, compare only against the last draft you sent, and check the result with an independent comparison before it goes out.

This guide covers both methods, the clean-redline routine, and the mistakes that cause trouble mid-negotiation.

What a redline is

A redline is a marked-up document that shows what changed between two versions. Inserted text is underlined or colored, and deleted text is struck through. In contract work, the redline lets the other side see exactly what you changed since the last turn, so they don't have to reread the whole agreement.

"Redline" and "blackline" usually mean the same thing. A clean copy, confusingly, can mean two things: the final text with every change accepted, or a redline free of noise. This guide uses "clean redline" for the second meaning.

Method 1: Track Changes, step by step

Use Track Changes when you are the one editing.

1. Open the document and go to the Review tab.
2. Click Track Changes so it is highlighted, or press Ctrl+Shift+E. Do this before your first edit.
3. To stop others from switching tracking off, open the Track Changes drop-down and choose Lock Tracking. You can set a password.
4. Make your edits. Use New Comment for explanations instead of typing notes into the text.
5. Choose a markup view in the Tracking group:
   • Simple Markup shows the final text with change indicators in the margin.
   • All Markup shows every insertion and deletion.
   • No Markup shows the text as if the changes were accepted.
   • Original shows the text before any changes.
6. To resolve changes, use Accept or Reject one at a time. The arrows next to those buttons offer Accept All Changes and Reject All Changes.

Two things to know. Word assigns each author's color automatically, and the color can change when someone else opens the file. Color settings also apply only to your computer, so don't tell anyone to "look at the blue changes." Instead, you can set one color per markup type, so all insertions share a color.

Method 2: Word Compare (legal blackline)

Use Compare when edits were made without tracking, when someone sends back a "clean" file, or when you want a redline against a specific earlier version.

1. Go to Review → Compare → Compare two versions of a document (legal blackline).
2. Under Original document, pick the baseline. That is usually the last version you sent.
3. Under Revised document, pick the new version.
4. Click More to open the settings. Choose which differences to mark: text changes, comments, formatting and so on. Set Show changes at to Word level.
5. Leave Show changes in set to New document. If you choose Original or Revised instead, Word modifies that file.
6. Click OK. Word builds a third document with the differences marked as tracked changes. Your two source files are not changed.

If either file already contains tracked changes, Word warns you. In the result, the original's tracked changes are treated as accepted, and the revised document's changes appear as tracked changes. To merge edits from several reviewers into one file, use Combine instead of the two-version compare.

For a deeper walkthrough of comparison options, see how to compare two Word documents.

Clean vs. dirty redlines

A dirty redline has noise in it:

• formatting flags in the margin
• changes from earlier rounds
• several authors' colors
• leftover comments
• paragraphs marked as deleted and reinserted because they moved

The substantive edits are in there somewhere, but the reader has to dig. Heavily marked documents also hide typos and spacing errors.

A clean redline shows only the text changes since the last draft the other side saw, against the right baseline, with nothing left over.

The clean redline routine

1. Confirm the baseline

Most bad redlines start with the wrong original. Your baseline should be the exact file you last sent, not your latest internal draft. A consistent naming convention makes this easy, for example:

MSA_v4_sent-to-Acme_2026-10-09.docx

Save sent versions somewhere they won't be edited again, such as a "Sent" folder or a read-only copy.

2. Normalize both files

• In each file, accept or reject all leftover tracked changes and delete resolved comments, so each one is a single plain version.
• Make sure both files use the same template and styles if possible. Style mismatches produce floods of formatting marks.
• Leave automatic numbering as it is in both files. Converting one file's numbering to plain text creates false differences.

3. Turn off formatting noise

In the Compare settings, uncheck Formatting unless formatting really matters for this document. On an existing tracked document, go to Review → Show Markup and uncheck Formatting to see only text edits and comments. Formatting tracking is on by default in Word. More detail is in ignoring formatting changes in a redline.

4. Read the result, not just the totals

Watch for moved text. Word recognizes a move only if the paragraph was moved unchanged. A moved paragraph that was also edited shows up as a separate deletion and insertion, so read both carefully.

5. Scrub before sending

Run File → Info → Check for Issues → Inspect Document to find hidden tracked changes, comments and personal metadata. If you are sending a non-editable redline, save it as PDF so the markup displays the same on every screen. Your firm or company may have its own rules on what goes out in native format, so check them.

Common redlining mistakes

• Editing before turning on Track Changes. Those edits are invisible in the markup.
• Comparing against the wrong version. The redline then shows too much or too little.
• Showing changes in the Original or Revised document. This overwrites a file you meant to keep.
• "Accept all" remnants. Changes were supposedly accepted and tracking was stopped, but traces remain in the file.
• Renumbering surprises. Accepting changes can break numbering and cross-references. Recheck section references afterward.
• Unscrubbed metadata. Author names, comments and old revisions can travel with the file.
• Trusting tracked changes on a returned draft. The other side may have made edits with tracking off. Compare their file against your sent version rather than relying on their markup. See how to audit a counterparty's redline.

Verify with an independent comparison before you send

Word's redline is only as good as the steps that produced it. Before sending, run a second, independent check: compare the last sent draft against the exact file you're about to send, using a different tool. Every change in that check should appear in your redline. Anything that doesn't is an untracked edit.

DocxDiff is built for this check. Drop in the two .docx files and you get a word-level redline. Insertions appear in green and deletions are struck through in red. Each change is numbered, so you can tick them off against your Word markup ("changes 1–18 match; change 19 isn't tracked").

• Privacy: The comparison runs in your browser, so a confidential draft isn't uploaded unless you sign in and save it.
• Cost: Comparing Word, Markdown and text files is free, including HTML and Markdown reports.
• Formatting: DocxDiff compares text, not formatting. That suits a substance check, but you'll still review formatting in Word.

When the other side returns a PDF or a retyped document instead of a .docx, opening it in Word to convert it can introduce artifacts and false differences. DocxDiff Pro compares PDFs directly with page-accurate redlines and moved-text detection. It can also OCR scanned PDFs, but only after you approve it.

Write a short change summary

A summary memo saves the reader time and shows that your markup is complete. Keep it to one line per substantive change:

Organize the summary by section. Leave out typo fixes and cross-reference updates, or group them on a single line.

If your verification tool numbers changes, cite the number next to each row. This page is general information about document tools, not legal advice. Consult a qualified professional about what a change means for your agreement.

Ready to check your next turn before it goes out? Compare two versions free at DocxDiff.

Frequently asked questions

How do I make a redline in Word if I forgot to turn on Track Changes?

Use Compare. Go to Review → Compare → Compare two versions of a document (legal blackline). Choose your earlier saved version as the original and the edited file as the revised version. Word builds a new document with all differences marked as tracked changes.

What's the difference between a clean copy and a redline?

A redline shows the changes marked up. A clean copy shows the final text with all changes accepted and no markup. Parties often exchange both, but practice varies, so confirm what the other side expects.

Why is my Word redline full of formatting changes?

Formatting tracking is on by default, and style differences between files get flagged. Uncheck Formatting in the Compare settings or in Show Markup to see only text edits.

Can DocxDiff create or edit the redline inside Word?

No. DocxDiff compares two versions and shows what changed in a numbered redline you can export as a report. You still make and send your edits in Word.

Does DocxDiff catch formatting changes Word flags?

No. It compares text at the word level. That makes it useful for confirming substantive edits, but formatting needs a separate review in Word.