Original text
Paste the earlier version, source code or draft.
Changed text
Paste the newer version to compare against the original.
Change summary
Line counts update after every comparison.
Diff result
Review added, deleted and modified lines.
What is this tool?
Text Diff Tool compares two versions of text or code directly in your browser. It highlights added, deleted and modified lines, shows inline word changes and can export a plain unified diff report.
All comparison, highlighting, copying and diff export runs locally in the browser. Pasted text is not sent to an API and is not saved to local storage.
Features
- Side-by-side and unified diff views with line numbers
- Inline word highlighting for small edits inside changed lines
- Options to ignore whitespace or letter case when matching lines
- Change summary for added, deleted, modified and unchanged lines
- Copy the report or download a .diff file without uploading your text
How to use
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Paste both versions
Put the older version on the left and the newer version on the right.
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Choose the view
Use side-by-side for review work or unified view for a compact patch-style result.
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Adjust matching rules
Turn on whitespace or case ignoring when formatting noise should not count as a change.
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Export the result
Copy the summary and unified diff, or download a .diff file for your notes.
FAQ
Can I compare code with this tool?
Yes. It keeps spacing visible, uses a monospace result view and works well for JSON, Markdown, HTML, CSS, JavaScript and configuration files.
Is my text uploaded?
No. The comparison runs in your browser and the tool does not upload, store or send the pasted content.
What do the colors mean?
Green lines are additions, red lines are deletions, yellow lines are modified pairs and neutral lines are unchanged.
Can it handle long documents?
Yes for normal browser-sized documents. Extremely large comparisons are capped by a local performance guard so the page stays responsive.