Compare two texts
Paste two versions of a text and instantly see what changed: lines found only in the first turn red, lines found only in the second turn green.
How to read the comparison result
Lines on a red background, marked with a − sign, appear only in the first text: they were deleted or edited. Lines on a green background, marked with a + sign, exist only in the second: they are additions, or the new version of a line that changed. Lines with no highlight are identical in both texts. The comparison uses the "longest common subsequence" alignment — the same principle behind the diff tools programmers rely on. That means if you insert a line halfway through a document, everything after it isn't flagged as different: the remaining lines are re-aligned correctly.
When comparing two texts comes in handy
Classic use cases: two revisions of a contract or a thesis, the draft and the edited version of an article, two lists you need to reconcile (guest lists, inventories, email lists), or two configuration files. The comparison works line by line, so it shines with text that has frequent line breaks. To keep things fast, each box is limited to 2,000 lines — more than enough for most documents.