Developer Tools tool
Diff Checker
Compare two blocks of text side by side and highlight the differences.
Compare two blocks of text and highlight additions, removals, and changes. Free online diff checker for developers, writers, and editors.
Original text
Changed text
Why people use this tool
Diff Checker compares two text blocks and highlights every difference, making it easy to spot changes between document versions, code revisions, or content drafts.
- Compare code changes between versions before committing or reviewing.
- Spot differences between document drafts, contracts, or content revisions.
- Verify configuration changes by comparing before and after versions.
How to use it
- 1Paste the original text in the left panel.
- 2Paste the changed text in the right panel.
- 3Review highlighted additions (green) and removals (red) in the diff output.
FAQ
Helpful answersWhat does the diff checker highlight?
It highlights added lines in green and removed lines in red, making it easy to see exactly what changed between two versions.
Can I compare code with this tool?
Yes. The monospace font and line-by-line comparison work well for code, config files, and any structured text.
Is there a file size limit?
The tool works in the browser, so it handles typical text comparisons well. Very large files may be slower.