Which regex flavor is this?

JavaScript / ECMAScript regex — the same engine your browser uses. Some PCRE features (lookbehind, named groups) work in modern browsers.

How do I use the flags?

Toggle g (global), i (case-insensitive), m (multiline), s (dotall), and u (unicode) with the checkboxes above the pattern.

No. The regex runs inside your browser tab — nothing leaves your device.

Developer Tools

Test JavaScript regular expressions live. Highlighted matches, capture groups, and full flag support.

Pattern

//gm

Preview

Reach us at hello@web-toolbox.in or support@example.com — we reply within 24 hours.

Matches

Match 1at index 36

support@example.com

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