How do I test regex patterns online?
Testing regex patterns online helps you validate and debug regular expressions before using them in production code.
Using an online regex tester:
- Paste your test text into the input field
- Enter your regex pattern
- See matches highlighted in real-time
- Review capture groups and matched values
- Adjust your pattern and instantly see results
Benefits of online testing:
- No need to write code or set up a development environment
- Instant visual feedback on what matches and what doesn't
- Test against multiple input samples quickly
- See capture groups and backreferences clearly
- Validate patterns before implementing in scrapers or validators
Common testing scenarios:
- Extracting email addresses from text
- Validating URLs or phone numbers
- Parsing log files or structured data
- Testing patterns for web scraping selectors
- Debugging why a pattern isn't matching expected content
Debugging patterns:
Online testers make it easy to iterate on patterns by showing exactly which parts match and where matches fail. This visual feedback is much faster than the write-run-debug cycle in code.