Text Diff

Text Diff compares two blocks of text and shows you exactly what changed between them, line by line.

Using a classic longest-common-subsequence diff — the same family of algorithm that powers version control — it highlights added lines in green, removed lines in red, and leaves unchanged lines neutral, so the shape of the edit is obvious at a glance.

A small badge counts how many lines were added and removed overall.

Comparing two versions of a config file, a draft and its revision, a pasted email thread, or two slightly different lists is the kind of task where the eye slides right past the one character that actually changed.

A proper diff removes that guesswork: it aligns the matching lines and surfaces only the real differences.

Because everything runs in your browser, you can compare sensitive documents — contracts, credentials, internal notes — without uploading them anywhere.

Paste the original on the left and the changed version on the right and the diff appears instantly, updating as you type.

You can copy a plain-text unified view of the result, with leading + and - markers, to paste into a ticket, a chat message or a code review.