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How to use Regex Tester

Type your regular expression and a test string, and the tool highlights every match live, showing groups and detailed match information.

Frequently asked questions

How does the regex tester work?

Enter your regex pattern and test string. Matches are highlighted in real-time, and you can see all matches, groups, and indices.

What regex flags are supported?

Common flags like g (global), i (case-insensitive), m (multiline), s (dotall), and u (unicode) are supported.

Can I test JavaScript-specific regex?

Yes, the tester uses JavaScript's regex engine, so all JavaScript regex features including lookbehinds and named groups work correctly.

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