Free online regex tester
Regex Tester
Test JavaScript regular expressions against sample text with match highlighting and capture groups.
Developer utility
Browser based
Runs on the current page
Copy-ready
Use the output where you work
No sign-in
Open the tool and get moving
Developer tool
Test Regex
Run JavaScript regular expressions against sample text and inspect matches.
dev@entwicklera.com
index 8
support@example.com
index 31
Built for developers
Small utilities for fast technical checks.
Entwicklera developer tools are made for everyday formatting, encoding, decoding, generation, and inspection tasks during implementation and debugging.
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FAQ
Regex Tester questions.
Which regex engine does this use?
It uses the JavaScript regular expression engine built into your browser.
Can I test capture groups?
Yes. Matches include capture groups when the expression contains grouped subpatterns.
Custom software