↔️ Text Diff Checker
Text Diff Checker compares two blocks of text line by line using the LCS algorithm — the same approach behind Git diff — and highlights the differences. It is line-level only: there is no word-level mode, so short lines give sharper results. Everything runs in your browser and very large texts may need chunking.
- PriceFree, no signup
- AlgorithmLCS, line-level
- UploadNever — local
- OutputHighlighted diff
Reading the diff output
| Change type | How it shows | Tip |
|---|---|---|
| Added lines | Marked in the modified side | New content you inserted |
| Deleted lines | Marked in the original side | Content that disappeared |
| Changed line | Shown as delete + add | Line-level, not word-level |
| Reordered lines | Shows as remove + add | Diff does not track moves |
| Whitespace-only change | Shows as a change | Check trailing spaces |
| Word-level precision needed | Not supported | One word per line as a trick |
📄 Original Text
📝 Modified Text
📊 Differences
Text Diff: Compare two text blocks and show differences
Text Diff lets you compare two text blocks and show differences. Upload two text blocks and get a diff view — all processed locally in your browser, with no uploads and no sign-up.
Compare two document versions
Compare two document versions. This is one of the most common reasons people reach for Text Diff — and it handles the job in seconds, entirely in your browser.
Find changes between text drafts
Find changes between text drafts. This is one of the most common reasons people reach for Text Diff — and it handles the job in seconds, entirely in your browser.
Review code or text edits
Review code or text edits. This is one of the most common reasons people reach for Text Diff — and it handles the job in seconds, entirely in your browser.
Everything You Need in a Text Diff
Powerful features that make Text Diff fast, private, and free.
Instant Processing
Conversion and validation happen as you type.
Developer-Grade
Built for accurate, standards-compliant results.
100% Private
All processing is local — no data is sent anywhere.
Copy & Export
One-click copy to clipboard for quick use.
Free Forever
No sign-up, no API keys, no limits.
Regex & JSON Support
Full regular expression and JSON validation built in.
How to Use
Paste the two texts
Put the original text in the left box and the revised text in the right. You can also paste code, config files, or any plain text you want to compare.
Run the comparison
The tool highlights lines or words that differ between the two, showing additions, deletions, and changes at a glance.
Review the highlighted differences
Scan the color-coded output to see exactly what changed. This is the fastest way to catch edits in contracts, code, or prose.
Copy or export the result
Copy the diff output for your records, or use it to reconcile two versions of a document.
Detailed User Guide
Compare text side by side for quick review
The diff tool highlights what was added, removed, or changed between two versions, line by line. It is built for reviewing edits to documents, code, and config files without manually scanning every line.
Word-level vs line-level differences
The tool can show differences at the line level for quick scanning or at a finer granularity for precise edits. Choose the granularity that matches your review task.
Everything runs locally in your browser
Your text never leaves the device, which matters when comparing drafts, legal clauses, or source code you would rather keep private.
Great for code reviews and changelogs
Paste two versions of a script or config and see the exact changes. This is especially handy when you have no version-control diff available.
Large texts may need chunking
Very long documents can be compared, but extremely large inputs may slow the browser. Compare section by section for the clearest results.
Read the diff like a changelog
Green highlights mark added text and red marks removed text, so a long edit collapses into a quick scan. Reading the diff top to bottom is often faster than re-reading both documents in full.
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