Diff Checker
Compare two texts and highlight the differences line by line
+4 added−4 removed1 unchanged
| 1 | 1 | The quick brown fox | |
| 2 | + | jumps over the lazy cat. | |
| 3 | + | Hello, TypeScript! | |
| 4 | + | This line is the same. | |
| 5 | + | And a new line was added. | |
| 2 | − | jumps over the lazy dog. | |
| 3 | − | Hello, World! | |
| 4 | − | This line is the same. | |
| 5 | − | One more line here. |
How to use / Why use this tool / FAQ
How to use
Paste the original text on the left and the modified version on the right. The diff result updates automatically with added (green) and removed (red) lines highlighted.
Why use this tool
Quickly spot differences between two versions of text, code, or documents. Switch between unified and split view. All processing is local — no files are uploaded.
FAQ
- What diff algorithm is used?
- A line-level LCS (Longest Common Subsequence) algorithm — the same approach used by git diff.
- Is there a text length limit?
- No hard limit. Very large texts may be slower due to browser memory, but typical documents work instantly.
- Is my text sent to a server?
- No. All diffing runs locally in your browser using pure JavaScript.