Regex Tester
Test regular expressions, highlight matches and explain them.
READY
regex_tester.tool
READY
//gi
Matches (2)
// HOW IT WORKS
The tool runs a regular expression against your test text and highlights every match and capture group in real time. It also reports syntax errors.
Example
Pattern \d{4}-\d{2}-\d{2} on '2026-06-21' → one match; group 0 = the whole date.
Notes
- Flags change behavior: g (all matches), i (case-insensitive), m (^/$ per line).
- It uses the JavaScript regex engine — some features (lookbehind, named groups) depend on browser support.