Paste two versions of a text and see every change highlighted, word by word or line by line. Use it to check what ChatGPT or Claude changed in your draft, review a config or compare two contracts. It counts the words added and removed, lists each edit and runs in your browser.
Free online diff checker. Compare two texts word by word or line by line, in an inline or side by side view, with ignore-whitespace and ignore-case options. Shows words added, words removed, percent changed and a list of every edit, which makes it useful for checking AI rewrites. Runs in the browser.
Changes show up here
Paste the original on the left and the new version on the right, or try the example.
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A three-sentence team email, rewritten by an AI assistant. The rewrite grew from 42 to 58 words, and 48% of the words changed. Most of the additions are filler, and “bugs” quietly became “issues”.
Hi team, We shippedWe're excited to announce that the new export feature went live on Tuesday. It lets you! You can now download any report as a CSV or PDF . A fewfile in just a few clicks. Several customers asked forhave requested Excel toosupport, so that's next on the list. Let me knowour roadmap. Please don't hesitate to reach out if you see any bugs.run into any issues. Best, Sam
+32
words added
−16
words removed
48%
of words changed
9
edits
Words mode suits text that reads as sentences. Lines mode suits text where every line stands on its own. Switching costs nothing, so try both on the same pair.
| Words | Lines | |
|---|---|---|
| Best for | Prose, emails, AI rewrites | Code, configs, CSV, logs |
| A changed sentence shows as | Only the words that moved | The whole line, with the changed words marked |
| Line breaks | Ignored with Ignore whitespace | Each line is compared on its own |
| Copy and download | Word diff with [-removed-] and {+added+} | Unified .diff patch |
The original on the left, the edited or AI-rewritten version on the right. You can also drop a file on each side.
Words for prose, Lines for code. Turn on Ignore whitespace or Ignore case to hide changes you don't care about.
Scan the highlights, check the word counts and the list of edits, then copy the diff or download a .diff file.
Paste the original on the left and the new version on the right, or drop a file on each side. Changes are highlighted as you type: removed text in red with a line through it, added text in green. Pick Words for prose and Lines for code, then view them side by side or in one unified column.
Paste your draft as the original and the AI rewrite as the changed version. The diff checker marks every word the model swapped, added or cut, counts the words on each side and lists each edit in order, such as "asked for" to "have requested". It's a quick way to spot filler and meaning changes before you accept a rewrite.
Use Words for prose, emails and AI rewrites, where a sentence changes a few words at a time. Use Lines for code, configs, CSV and logs, where each line is one unit. In Lines mode, a changed line still gets word-level highlights, so you can see exactly which part of the line moved.
Ignore whitespace treats reflowed paragraphs, extra spaces and changed indentation as unchanged, so only real edits show up. Ignore case treats "Export" and "export" as the same word. Both options change what counts as a difference, but the text you see on each side is always your original text.
It's the words added plus the words removed, divided by the total words in both versions. Two identical texts score 0% and two texts with no words in common score 100%. The example on this page, a short team email and its AI rewrite, scores 48%.
Inline shows one text with removed words struck through right before the words that replaced them, like tracked changes in Word. In Lines mode it becomes the unified layout from git diff and GitHub pull requests. Side by side puts the original and the new version in two columns, which suits long documents.
Yes. In Lines mode, Download saves a standard unified .diff file that git apply and patch can read. In Words mode, it saves a .txt with removed text in [-brackets-] and added text in {+braces+}, the same style as git diff --word-diff. Copy puts the same text on your clipboard.
No. The comparison runs in your browser with JavaScript, and nothing you paste or drop is sent to a server. That makes it safe for contracts, private code and unpublished drafts. There's no signup and no limit on how many comparisons you run.
Models differ in how much they rewrite. See how they rank before you pick one for your drafts.
Everything from model picks to CSV converters, with no account needed.