Diff Checker
Compare two texts and highlight the differences line by line.
All processing happens in your browser. Your data never leaves your device.Features
- Compare two texts side by side with color-coded differences
- Line-level diff highlighting with added (green) and removed (red) lines
- Summary showing total lines added and removed
- Support for large texts — handles files with thousands of lines
- Clean, readable diff output using the standard unified diff algorithm
How to Use the Diff Checker
- 1Paste the original text in the left input area
- 2Paste the modified text in the right input area
- 3Click "Compare" to generate the diff
- 4Review the color-coded output — green for additions, red for removals
Frequently Asked Questions
What diff algorithm is used?
This tool uses the standard diff algorithm (similar to Unix diff) via the 'diff' library. It produces accurate line-by-line comparisons suitable for code reviews, document comparisons, and content auditing.
Can I compare code files?
Yes. The diff checker works with any plain text including source code, configuration files, JSON, XML, and markdown. It preserves whitespace and formatting for accurate comparisons.
Is there a size limit?
There's no hard limit, but very large texts (hundreds of thousands of lines) may slow down due to browser processing constraints. For most practical use cases (files up to tens of thousands of lines), performance is excellent.