Paste two versions of a text and see precisely which lines were added, removed or left alone — with whitespace and case sensitivity under your control.
Not everything lives in git. Two versions of a contract, a config file pasted from a server, an email thread, a translated paragraph — all need comparing, and none of them belong on a stranger's server.
The tool computes the longest common subsequence of the two line lists — the same idea behind diff and git. Lines that appear in both, in order, are the unchanged skeleton; everything else is an insertion or a deletion. That is why moving a paragraph shows as a removal in one place and an addition in another rather than as a “move”.
The two gutter columns are the line numbers in the original and the changed text, so you can navigate back to either source. Use “changed lines only” once the diff gets long — reviewers rarely need the unchanged context in a browser.
Related: word counter, JSON formatter (format both sides first to make structural diffs readable).
No. The comparison runs in your browser, which makes it safe for contracts, configuration files and anything else you would not paste into a random website.
It collapses runs of spaces and tabs and trims line ends before comparing, so re-indented code or re-wrapped prose stops showing as changed. The output still displays the original lines.
A few thousand lines per side compare instantly. The algorithm compares every line against every other, so very large files (tens of thousands of lines) will feel slow — use git diff for those.
Not yet — comparison is line by line. A line that changed anywhere appears as one removal plus one addition.
No. The line comparison reports text removed from its old position and added at its new position. It does not classify those two changes as a move.