JA4 t13d1516h2_8daaf6152771_2c66ae2d0ce4

t13d1516h2_8daaf6152771_2c66ae2d0ce4

Headless Chrome — inferred from the User-Agent on its requests.

What this fingerprint encodes

Transport

TCP

TLS version

TLS 1.3

Server name

server name sent

Cipher suites offered

15

Extensions offered

16

ALPN

h2

The hello it was computed from

Recovered because the proxy now stores the pre-hash JA3 string alongside the digest. Every number below came out of this client's ClientHello; anything we cannot name in the IANA registry is shown as its raw value rather than guessed at.

Version

TLS 1.2

Cipher suites 15

• TLS_AES_128_GCM_SHA256
• TLS_AES_256_GCM_SHA384
• TLS_CHACHA20_POLY1305_SHA256
• TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
• TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
• TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
• TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
• TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
• TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
• TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
• TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
• TLS_RSA_WITH_AES_128_GCM_SHA256
• TLS_RSA_WITH_AES_256_GCM_SHA384
• TLS_RSA_WITH_AES_128_CBC_SHA
• TLS_RSA_WITH_AES_256_CBC_SHA

Extensions 16

• status_request
• signature_algorithms
• extended_master_secret
• signed_certificate_timestamp
• application_layer_protocol_negotiation
• supported_groups
• psk_key_exchange_modes
• server_name
• session_ticket
• ec_point_formats
• encrypted_client_hello
• compress_certificate
• 17613 (0x44cd)
• renegotiation_info
• key_share
• supported_versions

Named groups 4

• SecP256r1MLKEM768
• x25519
• secp256r1
• secp384r1

Point formats 1

• uncompressed

771,4865-4866-4867-49195-49199-49196-49200-52393-52392-49171-49172-156-157-47-53,5-13-23-18-16-10-45-0-35-11-65037-27-17613-65281-51-43,4588-29-23-24,0

Seen in live traffic

Connections

153

First seen

2026-09-03 17:11 UTC

Last seen

2026-10-09 23:49 UTC

Transport

TCP

JA3 hashes absorbed

153

The same client, 153 different JA3s

This one JA4 covers 153 distinct JA3 hashes. A JA3 hashes the cipher and extension lists in the order they arrived, so a client that shuffles them — which Chrome and its derivatives do on purpose — produces a new JA3 almost every connection and fragments into what looks like 153 unrelated clients. JA4 sorts those lists before hashing, which is why all of it lands here instead.

• 8c09ae10620432569355fa9c8663ecd0
• bfca6b3be2b5cd608585b01839a318ee
• cd7d45a7a5d16718b295b6b948ee9c31
• 47d4820f5521973549dc9a2f0054689c
• 7502a11aa15f4bc75b3b8ab9aaadfb67
• 520fdebf8bb3945f91e9a9a597b8ca2d
• 44e5073ba8132863288dc1dfd438ff2f
• aae105804a3a5dddd55669ce17f16f4e
• ad4a04a766d384bcb2040177a9946027
• 92dfb52ec71dc3963a2546e6cdc453e6
• 2538d65aae41bceacc4e4717c24e7f3e
• 89f76e0df085948ef0cbc011a7bcbd29
• … and 141 more

User-Agents seen on this fingerprint

• Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/153.0.8010.12 Safari/537.36 734×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Safari/537.36 Edg/153.0.0.0 519×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 Edg/154.0.0.0 168×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36 Edg/152.0.0.0 138×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/155.0.0.0 Safari/537.36 Edg/155.0.0.0 45×
• Mozilla/5.0 (compatible; AhrefsBot/7.0; +http://ahrefs.com/robot/) 22×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 13×
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36 Edg/152.0.0.0 9×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36 6×
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36 5×
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Safari/537.36 5×
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 5×
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Safari/537.36 3×
• Mozilla/5.0 (Linux; Android 15; 23049RAD8C Build/AQ3A.241006.001) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.8010.36 Mobile Safari/537.36 2×
• Mozilla/5.0 (X11; CrOS x86_64 14541.0.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36 1×
• Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Mobile Safari/537.36 1×
• Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Mobile Safari/537.36 EdgA/153.0.0.0 1×
• Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Mobile Safari/537.36 1×

A User-Agent is self-declared and trivially forged, so this names an observation rather than proving an identity. It is still the strongest signal available: the fingerprint comes off the TLS handshake and the User-Agent off the request that followed, and one client build keeping a stable JA4 while changing what it calls itself is a finding in its own right.

This entry is an observation, not a policy decision. It is here because the edge saw it, not because anyone reviewed it, and it blocks nothing on its own. Only the curated tier drives classification and banning.