Diff Viewer
A fast, privacy-first text diff tool. Paste two texts, see a live diff with line and character-level highlights, and share via a unique URL. No accounts required.
Features
- Side-by-side diff with line and character-level highlights, synchronized scrolling, and collapse
- Live updates on every keystroke via CodeMirror 6 merge view
- Auto-save with shareable URLs — edit links with write access and read-only links for sharing
- Export as unified diff, standalone HTML, PDF, or copy as rich text
- View raw unified diff via
?format=diffquery parameter - Deploy your own instance to Cloudflare in one click — zero configuration required
Programmatic Access
- REST API — create, read, update, delete diff sessions with JSON
- Content negotiation —
Accept: text/markdownor?format=diffreturns unified diff text - Conditional requests — ETag and If-None-Match support for efficient polling (304 Not Modified)
- Private sessions with edit token authentication
No cookies. No tracking. No user accounts. Sessions contain only your two texts and timestamps, and auto-expire after 90 days of inactivity.