Text Diff
Highlight what changed between two texts.
Runs entirely in your browser — nothing you enter is uploaded or sent to a server.
It compares line by line, so a small edit inside a line shows as a whole line removed and re-added — it's for spotting differences, not for merging changes. Read our full disclaimer.
About this tool
Paste an original and a changed version of any text and this tool highlights the differences line by line, using the classic longest-common-subsequence algorithm — the same idea behind git and code review diffs. Added lines are marked in the accent color, removed lines in red, and unchanged lines stay muted, with a running count of each. Handy for comparing drafts, config files, logs, or copy.
Try it
Change 'jumps over' to 'leaps over' and add a line, and the diff shows one removed line, one changed line's replacement, and the new line marked as added.
How to use
- 1Paste the original text on the left.
- 2Paste the changed text on the right.
- 3Read the combined diff below — additions, removals, and unchanged lines.
- 4Use the counts to see how much changed at a glance.
Features
- Line-by-line diff with added / removed / unchanged highlighting.
- Running counts of additions and removals.
- Handles insertions and deletions, not just replacements.
Frequently asked questions
Does it diff word by word or line by line?
Line by line — it compares whole lines, which is the most useful view for text, config, and logs. A changed line shows as a removed line plus an added line.
How do I find the difference between two texts?
Paste the original on the left and the changed version on the right; the tool lists every line as added, removed, or unchanged, with counts. It's the fastest way to see what changed between two drafts, configs, or logs.
Is my text uploaded anywhere?
No. The comparison runs entirely in your browser, so nothing you paste is sent to a server — safe for private drafts, config, or logs.
Can it handle large blocks of text?
Yes. It compares thousands of lines comfortably; a very large paste just takes a moment longer to render the highlighted result.
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