Developer Utilities · Free tool
Diff Checker
Paste two blocks of text and see what changed line-by-line. Great for contracts, code, and writing revisions.
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What it does
Paste two blocks of text — a previous and current version of a contract, a commit message, or a draft — and see exactly which lines changed. Unchanged lines appear grey on both sides; removed lines are red on the left, added lines are green on the right. The diff is a standard LCS-based line comparison, same idea as diff on a Unix shell.
For comparing structured text like JSON, reformat both sides first with JSON Formatter before running the diff — identical data can otherwise show as completely different if whitespace or key order shifted.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/diff-checker" width="100%" height="720" frameborder="0" loading="lazy" title="Diff Checker" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Paste the original text on the left.
- Paste the changed text on the right.
- Click Compare — scroll through the side-by-side result.
- Red = removed, green = added, grey = unchanged.
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Guides about this topic
- Productivity & Focus · GuideHow to compare text changesGenerate line, word, and character-level diffs for code, prose, and legal docs. Free, no-download tool comparison and workflow guide for instant use.
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