How to compare two texts
Paste the original on the left and the changed version on the right — the comparison runs instantly as you type. Removed lines show in red with a minus, added lines in green with a plus, and both sides keep their own line numbers so you can trace every change back to its source. Use Swap to flip the direction of the comparison.
Prettify before you compare
Minified JSON or XML diffs terribly — everything is one long line, so a single changed value marks the whole document as different. The Prettify button reformats each side with consistent indentation first (choose JSON, XML, or leave it on Auto to detect), turning an unreadable one-line diff into a precise line-by-line one.
Common uses
- Config changes — spot exactly what changed between two versions of a settings file.
- API responses — prettify two JSON payloads and see which fields differ.
- Documents & contracts — verify what was edited between two drafts.
- Code review — compare two snippets without committing anything anywhere.
Frequently asked questions
Is my text uploaded anywhere?
No — and this matters for diffs, which often contain configs, keys, or private documents. The comparison runs entirely on your device; nothing you paste is stored, logged, or transmitted.
What does "Ignore trailing whitespace" do?
Invisible spaces at the end of lines often creep in from editors and copy-paste. With this on, two lines that differ only by trailing spaces count as identical.
How is similarity calculated?
Unchanged lines divided by the total lines in the longer version. It's a quick gauge of how much survived between versions, not a formal metric.