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Regex Tester

Test regular expressions with live matching and capture group extraction. See matches highlighted as you type.

//
Highlighted Matches0 matches
Match Details

Matches will appear here...

Frequently Asked Questions

What regex flags are supported?
All standard JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky).
Why is my regex not matching?
Common issues: forgetting to escape special characters (. * + ? [ ] etc.), missing the global flag for multiple matches, or case sensitivity. Check the error panel for syntax errors.
Is my data sent to a server?
No. All regex testing happens locally in your browser. Your patterns and test strings are never transmitted.
How do I see captured groups?
Captured groups are shown in the matches panel. Each match displays the full match plus any captured groups (numbered and named).
Can I test regex for other languages?
This tool uses JavaScript regex syntax. Most patterns are compatible with other languages, but some features (lookbehind, named groups) may vary. Always test in your target environment.

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