Text / Code Diff

1. Paste the earlier version into Original and the newer one into Modified.
2. Press Compare. Added lines are marked with a plus sign, removed lines with a minus sign, and changed characters inside replaced lines are highlighted.
3. Turn on Ignore leading and trailing whitespace to hide indentation-only changes, or press Swap to reverse the direction.
4. Press Copy diff to copy the whole comparison as a unified diff.

The texts are compared line by line. Each change is shown with three lines of context and with its old and new line numbers. Within a block of replaced lines, changed characters get a stronger highlight, so a renamed variable or a fixed typo stands out.

Spaces and a missing final newline count as changes. Windows (CRLF) and old Mac (CR) line endings are converted to LF before comparing, so texts that differ only in line endings are reported as identical, with a note.

Copy diff produces a unified diff with @@ hunk headers, the format used by git diff and diff -u, so you can paste it into a code review, an issue or a chat. It includes every change, even when the page shows only part of a long comparison. With Ignore leading and trailing whitespace on, the patch may not apply cleanly to the original text.

Each input can have up to 250,000 characters and 10,000 lines. Large inputs that are very different may exceed the processing limit; compare smaller sections instead. For very large or complex changes, character highlights may be skipped, but the line diff and the copied patch stay complete.

The comparison runs in a background worker in your browser. The tool never executes, uploads or saves your text.

Like the rest of the site, this page uses Google Analytics and Yandex Metrica, including Metrica session replay. Tool events report only that the tool was opened or used.

The tool area is marked so that Metrica masks what you type and the results in its session recordings.