Regex Tester
Test regular expressions with live match highlighting and capture groups.
- No upload
- Browser-based
- Free
- No signup
- Text
Matches
Common patterns (click to insert)
Runs in your browser. Your text never leaves your device.
Frequently asked questions
- Is my regex pattern or test text sent anywhere?
- No. Everything runs in your browser via the native RegExp engine — nothing is sent to a server.
- Which regex dialect does it use?
- JavaScript's built-in RegExp (ECMAScript). This is the same engine used by Node.js, browsers, and most JavaScript tools.
- What do the flags mean?
- g = find all matches, i = case-insensitive, m = ^/$ match line breaks, s = . matches newline, u = full Unicode support.
- Can I see capture groups?
- Yes — each match lists its numbered capture groups ($1, $2, …) below the match text.