Text Diff Checker
Compare two texts side by side and see every added, removed and changed line highlighted.
Paste text in both boxes to see the differences.
How it works
Paste the original text on the left and the changed version on the right — the diff checker compares the two texts line by line and highlights the result instantly. Removed lines are marked red, added lines green, and when a line was edited the changed words inside it are highlighted so you can find the difference between two texts at a glance. The comparison runs 100% in your browser: unlike online diff tools that send your content to a server, your text never leaves your device — safe for contracts, code and anything confidential. Use Copy diff to get a unified diff with +/− prefixes.
Frequently asked questions
How do I compare two texts for differences?
Paste the original text in the left box and the changed text in the right box. The diff appears instantly: removed lines are marked in red, added lines in green, and changed words are highlighted within each line.
Is this diff checker safe for confidential documents?
Yes. Unlike many online diff tools that send your text to a server to compute the comparison, this diff runs entirely in your browser, so contracts, code and credentials never leave your device.
Can I compare code with this tool?
Yes. The comparison is line-based, which suits code well, and whitespace is preserved. Paste two versions of a file to see exactly which lines changed.