Regex Tester Online (JavaScript, Free)
Test regular expressions online with live match highlighting. Free JavaScript regex tester — runs locally, no upload.
Regular expressions match patterns in text — emails, URLs, log lines, and validation rules. Testing interactively saves time compared to editing code and re-running scripts.
Common regex use cases
- Validate email or phone number formats
- Extract data from log files
- Find-and-replace with pattern matching
- Debug form validation rules before deployment