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Regex Tester

Test regular expressions with live match highlighting and capture group inspection.

//g

Test String

Common Patterns

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About Regex Tester

Test and debug regular expressions online with live match highlighting and capture group inspection. RAW's Regex Tester shows matches as you type, highlights capture groups in different colors, and supports JavaScript regex flags. Perfect for building and validating patterns before using them in code.

How to use

  1. 1Enter your regular expression pattern in the top field.
  2. 2Set regex flags (global, case-insensitive, multiline, etc.).
  3. 3Type or paste test text in the input area.
  4. 4Matches are highlighted in real-time with capture groups shown separately.

Frequently Asked Questions

Which regex flavor does this use?
RAW uses JavaScript's built-in RegExp engine, which follows the ECMAScript specification. This is the same engine used in Node.js, Chrome, Firefox, and other JavaScript environments.
What regex flags are supported?
All JavaScript regex flags are supported: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky).
Can I see capture groups?
Yes. Named and numbered capture groups are displayed separately for each match, with different colors to distinguish them. This helps debug complex patterns with multiple groups.