Regex Tester & Debugger
Test and debug regular expressions in real-time. See matches highlighted, capture groups extracted, and get explanations. Free online regex tester.
Frequently Asked Questions
What regex flavors are supported?▼
This tool uses JavaScript's built-in RegExp engine. Most common regex patterns work including lookaheads, lookbehinds, and named groups.
Can I see capture groups?▼
Yes, all capture groups are highlighted and listed separately so you can debug complex patterns easily.
What flags are supported?▼
All standard JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky).
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