Regex Tester — Free Online, No Upload Needed
Test JavaScript regular expressions against sample text with match highlighting and groups.
Data & DevFreeNo uploadOffline-capable
Open the interactive regex tester tool — free, runs in your browser.
About this regex tester
Debug email, phone or log-parsing patterns against sample text with live match counts and highlighting, plus instant feedback on invalid patterns and bad flags.
How to use
- Type a pattern and flags.
- Paste sample text.
- Review highlighted matches and the match count.
Common use cases
- Test an email or phone validation pattern before shipping it.
- Debug a log-parsing regex against real sample lines.
- Check capture groups and flags interactively while learning regex.
Every file is processed locally in your browser. Nothing is uploaded, logged or stored, and there is no account to create.
Regex Tester FAQ
Which flavor?
JavaScript (ECMAScript) RegExp, with g/m/i/s/u/y flags.
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