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How do I test a regular expression?
Enter your regex pattern and test string below. Matches are highlighted in real time. Supports flags like g, i, m, and s.
//
Matches will appear here...
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F.A.Q. — Questions, answered
- What is Regex Tester?Enter your regex pattern and test string below. Matches are highlighted in real time. Supports flags like g, i, m, and s.
- Is Regex Tester free?Yes. Regex Tester runs entirely in your browser. No data is uploaded or stored.
- Does Regex Tester work offline?Yes. Once loaded, Regex Tester works fully offline except for the QR code generator which uses a pinned CDN with SRI.