How it works
1
Write a pattern
Enter your regular expression and toggle flags like global, case-insensitive and multiline.
2
Add test text
Paste the text to search — matches highlight as you type.
3
Inspect matches
See every match and captured group so you can refine the pattern.
Why use Regex tester
Instant feedback
Matches highlight live as you edit the pattern, so you can iterate quickly instead of guessing.
Capture groups spelled out
Each match lists its captured groups, making it easy to see what your parentheses actually grab.
Runs locally
Your patterns and test data stay in the browser — nothing is uploaded.
Frequent questions
Which regex flavour does it use?
JavaScript regular expressions, so patterns behave the same as they would in browser or Node.js code.
Which flags can I set?
The usual ones — global (g), case-insensitive (i), multiline (m), dotall (s), unicode (u) and sticky (y).
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