RegExp Tester
Test regular expressions with live highlighting.
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Test string
Highlighted
Matches
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About the RegExp Tester
- What does the RegExp Tester do?
- Test regular expressions with live highlighting. GeekTool runs the RegExp Tester entirely in your browser — input never leaves your device.
- Is the RegExp Tester free?
- Yes. The RegExp Tester is part of GeekTool, a free suite of 50+ developer utilities. No sign-up, no ads inside the tool, no quotas.
- Does the RegExp Tester send my data to a server?
- No. All processing is client-side JavaScript. Your input stays in your browser tab — we never see it.