Free Regex Tester
Test regular expressions with live match highlighting, capture group extraction, and common pattern presets. See matches update in real time as you type. No signup required.
100% free — runs entirely in your browser
Free Regex Tester Features
Visual regex testing with instant feedback
Flag Controls
Toggle global (g), case-insensitive (i), and multiline (m) flags.
Capture Groups
See all captured groups for each match with index positions.
Common Patterns
One-click presets for email, URL, phone number, and IP address validation.
Live Testing
See matches highlighted instantly as you type your pattern and test string.
FAQ
What regex flavor does this use?
JavaScript's built-in RegExp engine. This is the same regex engine used in Node.js, browsers, and most JavaScript/TypeScript projects.
What are capture groups?
Capture groups are parts of the pattern enclosed in parentheses (). They extract specific parts of a match. For example, (\d+)-(\d+) captures two number groups from '123-456'.
How do I test multiline strings?
Enable the multiline (m) flag. This makes ^ and $ match the start and end of each line instead of the entire string.
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