Text Diff
TextCompare two text blocks line-by-line using the LCS algorithm with inline highlighting to review edits and merge conflicting changes side by side.
About Text Diff
When you have edited a config, are comparing two versions of copy, or checking that a copy-paste matched, eyeballing line by line is slow and error-prone. This tool compares two pieces of text locally in your browser and highlights additions, deletions, and changes line by line so differences stand out instantly. The whole comparison runs in your browser with no upload, so sensitive contract clauses or code snippets are safe to paste. Tip: Bookmark this tool for quick access whenever you need text processing. All processing happens locally in your browser — no data upload, so feel free to paste private content.
How to Use
- Open the Text Diff tool page
- Enter or paste your data into the input area
- View the real-time results and use the copy button to get the output
Use Cases
- Config compare — Compare config files from two environments to find extra or missing fields fast.
- Copy proofing — Match old and new copy to flag changed sentences and avoid missed edits.
- Code review — Paste two function versions to see which lines changed as a lightweight diff.
- Log comparison — Compare a normal vs. failing run log to isolate the differing lines for debugging.
- Paste check — Confirm text copied from two places is identical, catching hidden character differences.
- Merge conflict review — Paste two sides of a merge conflict to see the diff clearly and decide the correct resolution.
- Translation accuracy — Compare original and translated strings side by side to catch missing or mistranslated segments.
FAQ
Is the comparison line-based or character-based?
It highlights differences primarily by line; for changed lines you can clearly see which line moved, making the overall changes easy to scan.
Do spaces and line breaks count as differences?
Yes. Trailing spaces, indentation, and blank-line differences are all detected — exactly what you need to find invisible mismatches.
Can it compare very large files?
Small to medium text is smooth; very long text (tens of thousands of lines) slows browser rendering, so compare in chunks or use a local diff tool.
Does it handle CJK text correctly?
Yes. It works at the Unicode level, detecting mixed-script and full-width/half-width differences.
Can I save the diff result?
You can copy the differences to save yourself; the tool keeps no text on any server and clears when you close the page.
Any browser compatibility requirements?
This tool works in all modern browsers (Chrome, Firefox, Edge, Safari). No plugins or extensions required.
Can I use it offline?
After initial load, most features work offline. The core logic runs entirely in your browser with no network dependency.
Comments
Comments are stored locally in your browser. Configure Giscus for cloud-based comments.