Regex Tester
See your regular expression's matches highlighted as you type.
100% private - files never leave your browser
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Build and debug regular expressions with instant feedback. Enter a pattern and flags, paste your test text, and see every match highlighted live along with a match count. It is ideal for validation rules, search patterns and learning regex. Everything runs in your browser.
How to use Regex Tester
- 1
Enter your regex pattern and flags.
- 2
Paste the text to test against.
- 3
See matches highlighted instantly.
Frequently asked questions
It uses JavaScript's built-in regular-expression engine.