Regex Tester
Test regex patterns in real time
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Full guide
How to Test Regular Expressions Online
Learn how to test regex live: flags, capture groups, match highlighting, common patterns, and pitfalls that break JavaScript RegExp.
About Regex Tester
A real-time regular expression tester with instant match highlighting, numbered capture group extraction, flag toggles (global, case-insensitive, multiline, dotAll), match count, and a built-in cheat sheet with common patterns. Test your regex against sample text and see matches highlighted live as you type. All processing runs locally using JavaScript's native RegExp engine. Essential for developers, data engineers, DevOps, and anyone writing search patterns or validation rules.
Regex Tester Features
- Live highlighting
- Capture groups
- Flag toggles
- Match count
- Cheat sheet
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