Write a regular expression, see matches highlighted in real-time. Supports all JavaScript regex flags.
Type a regular expression pattern in the pattern field and a test string below. Matches are highlighted in real-time as you type. Toggle flags to change matching behavior. All processing runs in your browser.
This tool uses JavaScript's native RegExp engine, which is ECMA-262 compliant. It supports all modern flags including dotAll (s) and unicode (u).
Parentheses in your pattern create capture groups. They let you extract specific parts of a match. Groups are shown beneath each match in the results list.
The global flag finds all matches in the string, not just the first one. Without it, only the first match is returned.
No. All regex processing runs locally in your browser. Nothing is sent to any server.