Compare two texts instantly and see exactly what changed — line by line, color-coded, with summary stats. No server, no sign-up, no tracking. Everything runs in your browser.
Original
Modified
Diff Result
Enter text above and click Compare to see the diff.
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How It Works
The tool implements a Longest Common Subsequence (LCS) algorithm in pure JavaScript — the same foundation used by git diff. It compares your texts line by line, then applies character-level diffing on changed lines so you can see exactly which characters were inserted or deleted.
All processing happens in your browser. No text is ever sent to a server.
When to Use a Text Diff Checker
| Scenario | What to look for |
|---|---|
| Code review | Changed logic, added/removed lines |
| Document revision | Edited paragraphs, reworded sentences |
| Config comparison | Environment differences |
| Translation QA | Structural alignment between source and target |
Tips
- Ignore whitespace — useful when comparing code reformatted by a linter or prettier.
- Case-insensitive — handy for comparing user-entered data that may have inconsistent capitalisation.
- Swap — quickly reverse the comparison direction to check the diff from the other side.
- Unified view — a single-column view familiar to git users (
+/−markers).
Format your code before diffing → SQL Formatter
Preview Markdown in your browser → Markdown Preview