TCP SYN (JA4T)

65535_2-4-8-1-3_1424_9

first seen 2026-07-28 15:01 · last seen 2026-10-12 10:29 · JSON

Distinct clients per day (last 30 days, peak 3/day)

Distinct clients are counted by IP-hash per complete UTC day — unlike observation counts this is insensitive to one chatty client, but NAT merges clients and address rotation splits them.

Decomposed attributes

TCP window65535
Option kinds2-4-8-1-3
MSS1424
Window scale9

Co-observed signals

Signals from other families seen in the same observation. A fingerprint spread thinly across many lower-layer signatures is a classic inconsistency signal.

TLS ClientHello (JA4)

fingerprintco-occurrences
t13d131000_f57a46bbacb6_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.7
t13d1516h2_8daaf6152771_e5627efa2ab14
t13d4312h1_c7886603b240_b26ce05bbdd61
t13d4412h1_fd39b124ee10_58ed7828516f1

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn050000_3658ef221638_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: wget 1.21.4, wget 1.25.0, wget 1.21.3.The fingerprint page shows the full measured match list. More on the catalog.7
ge11nn050000_b223a0ebb0b5_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: python-requests 2.34.2, python-requests 2.33.1, python-requests 2.32.3.The fingerprint page shows the full measured match list. More on the catalog.2
ge20nn09zhcn_58cd8a8d2455_000000000000_0000000000002
ge20nr07zhcn_f13648a20120_000000000000_0000000000002

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;3:1000;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p2
1:65536;2:0;3:1000;4:6291456;6:262144|15663105|7:1:0:220|m,a,s,p1
1:65536;2:0;3:1000;4:6291456;6:262144|15663105|9:1:0:220|m,a,s,p1

TCP SYN (p0f)

fingerprintco-occurrences
4:45+19:0:1424:65535,9:mss,sok,ts,nop,ws:df,id+:010
4:46+18:0:1424:65535,9:mss,sok,ts,nop,ws:df,id+:01
4:48+16:0:1424:65535,9:mss,sok,ts,nop,ws:df,id+:01
4:47+17:0:1424:65535,9:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.365
Mozilla/5.0 (iPhone; CPU iPhone OS 14_4 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Mobile/15E148 Safari/604.14
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.362
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.361

Country

fingerprintco-occurrences
CN · China11
ES · Spain1
DZ · Algeria1

Network (ASN)

fingerprintco-occurrences
AS4811 · China Telecom (Group)7
AS45090 · Shenzhen Tencent Computer Systems Company Limited4
AS57269 · DIGI SPAIN TELECOM S.A1
AS33779 · Wataniya Telecom Algerie1

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprintlinked observations
q13d0310h3_55b375c5d22e_cd85d2d889182