Regex Tester
Test JavaScript regular expressions against sample text with live match highlighting, capture groups inspection and syntax error reporting.
Matches (2)
hello@jrtrove.com
support@example.org
What powers the Regex Tester
Live JavaScript regex evaluation
Match list with indices and capture groups
Flag toggles (g, i, m, s, u, y)
Syntax error reporting
Match count badge
Why the Regex Tester is different
Browser-native
The Regex Tester runs entirely in your browser. Input is processed locally — never uploaded, never logged, never cached anywhere outside your device.
No artificial limits
No daily quotas, no character ceilings, no "upgrade for more" walls. Every feature is the complete feature — the same on the first use as the thousandth.
Production-grade quality
Built to the same engineering bar as paid SaaS tools — accurate algorithms, audited logic, responsive design and accessibility-tested interactions.
Common use contexts
- Pattern development for search/replace
- URL routing rule debugging
- Input validation rule testing
- Log parsing pattern creation
Private and secure
Zero upload
All processing happens in your browser. Input is never transmitted, logged or cached.
Works offline
Once the page loads, the tool runs without an internet connection. No network calls happen during use.
No tracking
No accounts, no cookies for tool state. Only aggregate analytics count visits at the page level.