Skip to content
Toolify
Developer

Regex Tester

Build and debug regular expressions with instant feedback. Enter a pattern and test string, toggle flags like global and case-insensitive, and see every match highlighted along with capture groups. Uses the native JavaScript regex engine, safely, right in your browser.

/
/g

Up to 50,000 characters.

How to use the Regex Tester

  1. 1Enter a pattern. Type your regular expression (without the surrounding slashes).
  2. 2Set flags. Toggle global, ignore-case, multiline, and other flags as needed.
  3. 3Add test text. See matches highlighted and listed with their capture groups as you type.

Frequently asked questions

Which regex flavor is used?

It uses the JavaScript (ECMAScript) regular expression engine. Most common syntax is shared across languages, but some advanced features differ.

Is my test data private?

Yes. Matching runs locally in your browser, so your pattern and text never leave your device.