Runs locally in your browser
Text Diff
Compare two blocks of text line by line. Added and removed lines are highlighted instantly without sending either version to a server.
✓ Compared locally in your browser
Compare text line by line
Paste the earlier version on the left and the changed version on the right. The result keeps matching lines in context, marks deletions in red, and marks additions in green with original and new line numbers.
Useful for code, configuration, and documents
Line comparison helps review edited configuration, API responses, generated output, lists, release notes, and document revisions. Download the prefixed result when you need a simple portable record of the changes.
Frequently asked questions
How are the two texts compared?
The tool compares normalized lines and uses a longest-common-subsequence algorithm to identify unchanged, removed, and added lines.
Does Text Diff compare individual characters?
This version compares complete lines. A changed line appears as one removed line followed by one added line, which works well for configuration, code, lists, and documents.
What happens with very large text?
To prevent the browser from allocating an excessively large comparison matrix, very large inputs use a simplified comparison that preserves matching lines at the beginning and end.
Are the compared texts uploaded?
No. Both texts and the comparison result remain in your browser.