No. Uses the native browser JavaScript RegExp engine — nothing is sent to any server.

Which flags are supported?

g (global), i (case-insensitive), m (multiline), s (dotAll).

What patterns are in the library?

12 pre-built: email, URL, phone, date, IPv4, hex colour, credit card, HTML tags, and more.

Yes — all JavaScript regex syntax including lookaheads and lookbehinds.

A transparent textarea overlays a highlighted div — matches render in real time as you type.

Test regular expressions with live match highlighting and plain-English explanations for every token in your pattern.

Your files never leave your device. Processed locally. 100% private.

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Complete your task perfectly in just three straightforward steps.

Type your regex or choose from the 12-pattern library.

Enter text to match against — all matches highlight in real time.

Every regex token gets a plain-English label: anchor, quantifier, group, class, escape, literal.

Everything you need to know about the Regex Tester & Explainer.

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