Text Diff
Compare two blocks of text and view the differences in unified or side-by-side format. Runs entirely in your browser — nothing is uploaded or stored.
Frequently Asked Questions
What diff algorithm is used?
The diff npm package uses Myers' diff algorithm — the same algorithm used by Git. It produces minimal diffs.
What do the +/- symbols mean?
Lines starting with + were added (present in the right/modified text but not the left/original). Lines starting with - were removed (present in the original but not the modified). Lines with no prefix are unchanged.
Is there a size limit for the text I can compare?
There is no hard limit, but very large texts (hundreds of thousands of lines) may be slow to diff in the browser. For large files consider using git diff on the command line.
Is my data private?
Yes — completely. Everything runs locally in your browser. Nothing is sent to any server, and nothing is retained after you close the tab.
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