Skip to main content

Regex Tester

Test regular expressions against strings.

✓ Free ✓ No Sign-up ⚡ Instant Developer Tools

Regex Tester

Test regular expressions against strings.

/ /

What is Regex Tester?

Regex Tester tests a regular expression pattern against a test string in real time.

How Does It Work?

The tool uses JavaScript's RegExp constructor along with matchAll() to find all matches.

Common Use Cases

  • Pattern development - Develop and debug regex patterns.
  • Learning regex - Test patterns from a tutorial.
  • Data extraction - Search for email, URL, or date-format patterns.
  • Input validation - Test a validation regex before implementing it.
  • Log parsing - Extract data from a log file.

Frequently Asked Questions

Q: Why doesn't my regex match?

A: Make sure special characters are escaped correctly and that you've used the "g" flag for all occurrences.

Q: Does it support all JS regex features?

A: Yes, including lookahead, lookbehind, and named groups.

Q: How do I see captured groups?

A: Groups are displayed alongside the main match.