Text Diff
Compare two blocks of text and highlight additions, deletions, and unchanged lines. Useful for config reviews, copy edits, and log snippets when you do not want to paste sensitive diffs into an online checker. All comparison happens locally.
Runs in your browser. Nothing is uploaded.
About this tool
Compare two text blocks with a line-based diff (Myers via the diff library). Additions and deletions are highlighted; copy a simple unified-style patch from the tool bar. Swap panes to reverse the comparison without re-pasting.
How to use: paste 'before' on one side and 'after' on the other. Scan the highlighted lines, then copy a patch for a ticket. Useful for config reviews and copy edits you would rather not paste into an online checker.
Example: two versions of a .env file show which keys changed. Whitespace-only lines still count as line changes. This is not a word-level semantic diff. Copy the patch into a ticket instead of screenshots when you can.
Both sides stay in memory in this tab. Sensitive diffs are not sent anywhere. Related: JSON formatter if both blobs are JSON. Line-based means a reformatted paragraph may look noisier than a word processor's track-changes. After load, comparing files works offline.
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