Regex Tester

Test regular expressions live

Pattern

//g

Test string

Matches (2)

Contact us: ada@example.com or linus@kernel.org for help.

#1ada@example.com@ 12

#2linus@kernel.org@ 31

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About the Regex Tester

Test regular expressions online with live match highlighting, capture group inspection, and full flag control (g, i, m, s, u). As you edit the pattern or test string, matches highlight instantly and each match lists its position and capture groups — perfect for debugging JavaScript regex before it ships.

How to use

1Enter a regex pattern between the slashes.
2Toggle flags like ignore-case or multiline.
3Paste a test string and inspect highlighted matches and groups.

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Regex Tester is part of DevKit — 100 free, privacy-first tools for developers, students, and everyone, built by Minhazul Ashim. Everything runs in your browser; your data never leaves your machine.