JA3 / JA3N passive TLS fingerprint
Paste a JA3 string and it recomputes the JA3 hash, computes the permutation-stable JA3N, decodes the fields, and flags GREASE values.
Security & WAFHashed in your browser. Nothing is uploaded.
API endpointGEThttps://ronutz.com/api/v1/ja3-tls-fingerprintDocumented, not served. Opens the specification.
References
- Salesforce Engineering: Open Sourcing JA3 (field order, delimiters, empty fields, MD5; published string->hash examples)
- RFC 8701: Applying GREASE to TLS Extensibility (the reserved 0x?a?a values excluded from JA3)
- TLS extension permutation and JA3N (Chrome/Firefox randomize extension order; JA3N sorts extensions for a stable hash; JA4 is the successor)