Text Diff Online — Side-by-Side Line Diff
Compare two free-text blobs side by side with line-level highlighting. Optional ignore leading/trailing whitespace per line. Complements JSON Diff — everything stays local (documented size caps).
How comparison works
Paste left and right, optionally ignore leading/trailing whitespace per line (diffLines semantics), then Compare. Copy a unified +/- diff.
Options
Examples
Changed line
Left
Right
Append line
Left
Right
Related tools
For structural JSON, use JSON Diff. Back to the utilities hub.
Text diff FAQ
Free-text comparison
Why not unified-only view?
The accepted layout is side-by-side. A unified +/- copy remains available for the clipboard.
Size limits?
100,000 characters or 5,000 lines per pane — beyond that you get a too_large error.
3-way merge / apply patch?
Out of scope for v1.
JSON Diff vs text?
JSON Diff compares JSON structure. This tool is free-text line-by-line.
Windows CRLF vs Unix LF?
Line endings are normalized to LF before comparison — pasting Windows text against Unix text will not create false positives from \r alone.
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