Regex Tester
Test JavaScript regular expressions live. See every match highlighted with capture groups, match indexes and instant syntax errors.
How to use
- Enter your regular expression and toggle the flags you need.
- Paste or type the text you want to test against.
- Review the highlighted matches and the capture-group list below.
What is Regex Tester?
A live playground for JavaScript regular expressions — the same RegExp flavor used in browsers and Node.js. Enter a pattern, pick flags such as g (global), i (ignore case) or m (multiline), and every match is highlighted in your test text instantly.
The match list shows each match, its index and all capture groups, which makes debugging complex patterns much faster than trial and error in code.
Frequently asked questions
Which regex flavor does this use?
JavaScript RegExp (ECMAScript) — the same engine as your browser console and Node.js. Named groups and lookbehind are supported in modern browsers; recursive patterns are not.
What do the g, i and m flags do?
g finds all matches instead of stopping at the first; i makes matching case-insensitive; m makes ^ and $ match the start and end of each line. The s flag lets . match newlines and u enables full Unicode matching.
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