Online Text & Code Diff Comparison Tool
Compare documents, source code, JSON payloads, and confidential contracts completely inside your browser. Features side-by-side split view, inline unified diffs, intra-line character-level highlighting, and standard patch export with zero server transmission.
#How to Use This Tool
#Mathematical Formula & Standards
#Edge Cases & Technical Considerations
Surrogate Pairs and Multilingual Unicode
Handles multibyte UTF-8 characters, emojis, and non-Latin scripts (Japanese Kanji, Turkish diacritics, Cyrillic) without splitting code points or distorting offsets.
Mixed Line Endings (CRLF vs LF)
Normalizes Windows (\r\n) and Unix (\n) line endings automatically so cross-platform file comparisons only highlight genuine content modifications.
Fine-Grained Intra-Line Character Highlighting
When a line contains subtle edits (such as a single changed variable name or modified number), the diff engine highlights the exact character-level mutation inside the line.
#Frequently Asked Questions
Q:Are my confidential documents, contracts, or code uploaded to any server?
No. All text comparison and Myers diff computations run 100% locally in your browser memory via an isolated Web Worker. Zero bytes are uploaded to remote servers.
Q:Can I export the diff as a Git-compatible patch file?
Yes. Click "Download .diff" to export a standard RFC unified diff patch that can be applied directly using git apply or patch.
Have feedback or feature requests?
Help us improve this utility. Share suggestions, report edge cases, or request new features directly.
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