Original Text
Modified Text
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113 chars
0.00 ms
UTF-8
Diff Checker (Offline & Secure)
Free online diff checker — compare two texts or code blocks side by side with character-level additions and deletions highlighted. Works entirely in your browser.
How to use Diff Checker
- Paste or type 'Original Text' in the left panel and 'Modified Text' in the right panel.
- Insertions are highlighted in green and deletions in red, with line numbers.
- Both panels are editable — changes update the diff view in real time.
- Click 'Clear Both' to reset both panels.
Edge Cases & Important Considerations
- Very large files (100K+ lines) may cause the diff engine to slow down.
- Binary content is not supported — paste text or code only.
- The diff is computed character-by-character, not word-by-word.
Keyboard Shortcuts
- Ctrl/Cmd + K — Open Command Palette to switch tools instantly.
Frequently Asked Questions
Is this Diff Checker safe for sensitive corporate data?
Yes, 100%. All processing runs client-side in your local browser memory. No text, tokens, payloads, or logs are ever transmitted to any remote server or analytics engine.
Can I use this tool offline?
Yes. Because this tool runs strictly on client-side JavaScript with zero external API dependencies, once loaded it functions completely offline.
100% Client-Side Privacy Guarantee
All inputs are processed entirely inside your browser's memory using JavaScript. No data is ever transmitted to any server. Your tokens, JSON payloads, cURL commands, and timestamps never leave your machine.