Web
Regex Tester
Test JavaScript regular expressions live. Highlights matches, capture groups and quantifiers in real time.
Groups
- #1 ada@example.com→ ["ada", "example.com"]
- #2 grace@navy.mil→ ["grace", "navy.mil"]
Why use our Regex Tester?
100% private
Everything runs in your browser. Your data never leaves your device — safe for production payloads.
Instant results
No round trips, no rate limits, no login. Format, validate and inspect megabytes of JSON in milliseconds.
Standards-first
Follows RFC 8259 / ECMA-404 exactly. Reports errors with precise line and column diagnostics.
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