Text Diff Checker
Compare two texts line by line and spot every change.
100% in your browser — nothing uploadedPaste the original text on the left and the changed version on the right to get a line-by-line comparison: added lines are highlighted in green with a + marker, removed lines in red with a −, and a summary counts every change. It uses the same Myers algorithm found in Git, so the diff is minimal — only real changes get flagged. Options let you ignore letter case or trailing whitespace when they don’t matter.
It’s handy for reviewing document revisions, comparing configuration files, checking contract edits, or seeing what changed between two versions of code or SQL. The comparison runs entirely in your browser with JavaScript — neither text is uploaded anywhere, so it’s safe for confidential drafts, credentials, and client data.
FAQ
Is my text uploaded anywhere?
No. The comparison runs entirely in your browser with JavaScript — both texts stay on your device. That makes it safe for contracts, unreleased copy, code, and anything confidential.
Why does a changed line show as removed plus added?
The comparison is line-based: when a line’s content changes, the old version disappears and a new one appears, so you see one − line followed by one + line. This matches how Git and most diff tools report changes.
Is there a size limit?
Each side can have up to 20,000 lines, which covers most documents and source files. Past that limit the tool shows a clear message instead of trying anyway. Below it, the comparison keeps the page responsive for typical documents; two very large files with almost nothing in common can still take a few seconds, and the tool warns you before it starts.