Regex Tester
Write a pattern, toggle flags, and see every match highlighted with capture groups listed — plus a cheat sheet of the most-used regex tokens.
FAQ
Which regex flavor is used?
JavaScript (ECMAScript) regex, as executed by your browser — lookbehind, named groups and unicode flags are supported in modern browsers.
Why does my pattern match nothing?
Check escaping (\. for a literal dot), anchors (^ $) and flags — case-insensitive matching needs the “i” flag.
Can I test global replacement?
Enable the “g” flag and the tester lists every match — the same way JavaScript's replace with /g would find them.