Regex Tester
Test regular expressions against sample text and inspect matches.
Pattern and flags inputs
Match list with positions
No signup or server processing required
Pattern setup
Use standard JavaScript regex patterns and flags.
Matches
Review values and match positions to understand the pattern.
team@example.com
Index: 0
support@toolharbor.dev
Index: 30
Common use cases
- Checking patterns during form validation work
- Testing search-and-replace logic before coding it
- Teaching teammates what a regex actually matches
FAQ
Which regex engine does this use?
It uses the browser's JavaScript regular expression engine, which matches many frontend use cases closely.
Can I test flags like global or case-insensitive?
Yes. You can enter standard JavaScript regex flags such as g, i, and m.
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