Compare Two Documents to Check Proofreading Edits

To compare two documents after a proofread, put the text you sent out and the text that came back into a text diff, which shades every character that differs between them. That shows you what the proofreader changed, so you can confirm that each correction landed and that nothing else moved. It is a comparison step, not a proofreading tool or a grammar checker, and it only reports what differs between the two versions you paste.

Why document comparison beats a second read of proofread text

Reading the proof again tells you whether the text still sounds right, but a text diff shows exactly which characters changed from the version you sent. A diff is a view that highlights the differences between two pieces of text.

Where a visual review of proofread text fails

Small edits are exactly what a second read tends to miss. An extra comma after a clause, a missing space before a bracket, or one wrong letter in a surname still leaves the sentence readable, so a reader focused on meaning keeps going.

Nothing on the page flags these spots. Whether you read the two versions in turn or side by side, finding them is up to you.

What a text diff shows that reading cannot

A text diff highlights every place where the two texts differ and leaves the rest alone. The sakuttoAI diff tool colors lines found only in the original red and lines found only in the proofread version green.

Within a changed pair of lines, it also darkens the exact characters that differ, so a single added comma stands out. It tells you what changed, not whether the change is correct; that call is still yours.

How to compare two documents with a text diff tool

To compare two documents, paste the original you saved and the proofread version into the two boxes, then go through each highlighted change. The sakuttoAI text diff tool works on pasted text rather than uploaded files. It finds the differences between two documents even when neither one has tracked changes or other markup.

Save the original before it goes to the proofreader

Before you send the manuscript out, copy the text of the current version into a separate file. A diff needs both versions, and the copy you keep at that point becomes the left-hand text later.

For a Word manuscript, paste its text into a plain-text file. Put the review round and the date in the file name so you can find it quickly when the proofread version comes back.

Paste both versions into the diff and read the highlights

Put the original in the Before box on the left and the proofread version in the After box on the right; the highlights appear automatically. Added text is green, deleted text is red, and the counters above the result show how many lines were added and deleted.

Swapped inputs turn every addition into a deletion. The Swap button switches the two boxes back.

The up and down arrow buttons in the toolbar jump from one change to the next. The toolbar also shows your position out of the total, so you can tell when you have reviewed every change.

Sort every change: typo, wording, punctuation or name

Assign each change a single label as you go, so each change comes down to one question. Here are the labels and what to check for each.

A diff shows that the text changed, but not the reason. If a change needs explaining or you disagree with it, write that down in a comment or your own list and return it to the proofreader.

Compare Word documents and PDFs by copying the text

The tool works on text rather than files, so comparing Word documents or PDFs means copying the text from each and pasting it in. Pasting into the two input boxes is the only way to get text in; there is no upload button.

As a result, the comparison covers wording only. The steps are identical for a Word file, a PDF, an email or a web page.

Copy the text out of Word, then compare

Open both Word files, select and copy all of the text in each, and paste one into each box. The version you sent goes on the left and the returned one on the right.

Bold, fonts and page layout do not survive in a plain-text box, so an edit that only changed formatting will not appear in the diff. Each Word paragraph usually comes through as one line, so an edited paragraph shows up as a changed line with the edited characters shaded.

PDF text can add line breaks and formatting noise

Copying from a PDF can insert line breaks the author never typed, and the diff treats each one as text. Because the tool compares whole lines first, two copies that break in different places will show changed lines even when the words are identical.

Check the pasted text before reading the highlights. If it has been cut into short lines, copy from the Word or plain-text source of both versions instead.

Track Changes in Word versus a text diff

Track Changes records edits inside the Word file while they happen, whereas a text diff compares two finished texts, so they suit different situations. Track Changes works well when the proofreader edits in Word and turns it on first.

A diff is the better fit when the text returns as a clean copy, in an email or as a PDF, because it only needs the two versions, not a record of the edits. In both cases, you still decide on each change.

Proofread in stages and record a diff at each pass

When a manuscript goes through several rounds, a diff after each pass shows which pass changed what. Each hand-off then leaves its own record of how the document changed. When a bad change surfaces late, you can trace the pass that introduced it rather than comparing the first draft against the final one.

Three passes: typos, wording, final consistency

Split proofreading into three passes and take a diff after each one. Since every pass has a single job, the diff that follows it only has one type of change to review.

1. First pass: typos and grammar.
2. Second pass: wording and structure.
3. Final pass: consistency across the whole document.

Keep every returned version as a separate file, and always paste the previous version on the left. That way the diff shows only the changes from that pass.

Merge edits from two proofreaders into one manuscript

Put one proofreader's version on the left and the other's on the right, then resolve each difference with the merge buttons. Each change has two arrow buttons, Use left and Use right. Use left copies the changed block from the left text into the right text, and Use right does the opposite, so the side you copy from stays unchanged.

Once every difference is resolved, the tool shows No differences and both boxes contain the same text. The merged text exists only on the page, so copy it somewhere before closing the tab.

Check terminology consistency, then confirm with a diff

After standardizing a term, compare the before and after text, and the diff lists every place the term was changed. For example, a document might call the same person a "user" in some places and a "customer" in others.

Search for both words, pick one, and replace the other. Paste the pre-replacement version on the left and the new one on the right. The shaded words are the only places that changed, which makes it easy to spot a replacement that hit a word you meant to keep.

Use cases: book editing, web updates and press releases

Run a comparison every time a text changes hands, since each hand-off is a point where a requested edit can get lost or an unrequested one can slip in. Books, web articles and press releases differ only in which two versions sit side by side.

Book manuscripts across each review hand-off

Compare at each hand-off rather than just at the end. When a book goes from the author to an editor, back to the author to confirm, and on to final proofing, save the text at each step and check every returned version against the one you sent.

Editors call the result a redline, a marked-up view of what was removed and what was added between two versions. In this tool, deletions are red and insertions are green.

Web article updates and a change log

Put the published text on the left and the updated text on the right; the shaded lines become your change log. Paste that list into your notes with the date so the next editor knows what changed and when. It also confirms that an update only touched the paragraphs you intended.

Press release final review against the approved draft

Before the release goes out, paste the approved draft on the left and the final version on the right. Every difference that appears is a change no one approved, so sign off on it or undo it.

If the two texts are identical, the tool shows No differences. That only covers the words, so check the formatting in the document yourself.

Confidential drafts stay in your browser

The comparison happens in your browser, and the tool does not send pasted text to a server. Using this tool to compare text online does not involve uploading it.

That applies to the tool alone. Copies of the texts you keep in files or email fall outside it, so store them the way you would any draft.

Summary: compare two documents at every review round

Save the original, then compare two documents after every review round and sort each change by type before you accept it. Paste each returned version against the one you sent, and read every highlight with the arrow buttons. When two proofreaders work on the same text, compare their versions and settle each difference with Use left or Use right.