TLS_AES_256_GCM_SHA384

TLS 1.3 | 256-bit Recommended

Cipher Suite Details

Cipher Suite Name
TLS_AES_256_GCM_SHA384
Hex Value
0x1302
Decimal Code
4866
TLS Version
TLS 1.3
Security Level
256-bit
Recommended
Yes

What is TLS_AES_256_GCM_SHA384?

TLS_AES_256_GCM_SHA384 provides 256-bit security using AES-256 in GCM mode with SHA-384. It offers a higher security margin than AES-128, suitable for government and military applications requiring long-term secrecy. AES-256-GCM is approved for TOP SECRET data in the U.S. government (NSA Suite B). However, AES-256 is approximately 40% slower than AES-128 due to additional rounds (14 vs 10). For most commercial applications, the extra security is unnecessary. TLS 1.3 mandates support for this cipher suite. It is commonly offered as a fallback after TLS_AES_128_GCM_SHA256.

Role in JA3 Fingerprinting

The TLS_AES_256_GCM_SHA384 cipher suite is part of the TLS Client Hello that JA3 analyzes. Cipher suite order and selection are key indicators of browser type and version.

JA3 Format: TLS_VERSION,CIPHERS,EXTENSIONS,CURVES,POINT_FORMATS

Different browsers prioritize different cipher suites (Chrome prefers ChaCha20 on mobile, Firefox prioritizes AES-GCM, etc.), making cipher suite ordering a reliable fingerprint.

Test Your Cipher Suites

See which cipher suites your browser advertises, including TLS_AES_256_GCM_SHA384.