Regex Tester
Test a regular expression against sample text with live match highlighting.
Enter a regular expression and test text to see every match highlighted live, along with capture groups for each match.
Your files and text are processed locally in your browser — nothing is uploaded to a server.
Regex Tester tool
How to Use Regex Tester
- Enter your regular expression and flags.
- Paste sample text to test against it.
- Matches are highlighted automatically.
Features
- Live match highlighting
- Shows capture groups per match
- Supports standard JavaScript regex flags
- Clear error message for invalid patterns
Frequently Asked Questions
Which regex flavor does this use?
It uses standard JavaScript regular expression syntax, as supported by your browser.
Can I test multiline patterns?
Yes, enable the 'm' flag for multiline matching against text with line breaks.