Text diff checker
Paste the old and new versions to see what changed, line by line and character by character.
How to use
- Paste the original on the left and the changed version on the right.
- Removed (−) and added (+) lines appear below, with the changed characters marked.
- Unchanged lines are shown dimmed for context.
Questions
How does the comparison work?
A longest-common-subsequence diff by line; a removed line followed by an added line is then compared character by character.
Is a single changed space shown?
Yes. Whitespace is compared like any other character.
How long can the texts be?
Up to 4 million line pairs (for example 2,000 × 2,000 lines).
Is it safe for confidential text?
The comparison runs inside your browser; the text is not uploaded or stored.
Can I compare by word?
Not yet: by line and by character only.
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