TCP SYN (JA4T)

65535_2-4-8-1-3_1240_9

first seen 2026-07-01 17:02 · last seen 2026-08-21 17:42 · JSON

Distinct clients per day (last 30 days, peak 1/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
MSS1240
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
t13d1516h2_8daaf6152771_d8a2da3f94cd Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d1514h2_8daaf6152771_43ade6aba3df1
t13d1516h2_8daaf6152771_806a8c22fdea Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 151.0.7922.137, chromium 151.0.7922.34, +24 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d1515h1_8daaf6152771_de4a06bb82e31

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr13enfi_4ca454722327_000000000000_0000000000001
ge20nn030000_80b089f68b8e_000000000000_0000000000001
ge20nr13enus_05d774e75578_000000000000_0000000000001
ge11nn13enus_9db22d02e17a_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 149.0.7827.102, +59 more.The fingerprint page shows the full measured match list. More on the catalog.2
4:16777216|16711681|0|m,p,a,s1

TCP SYN (p0f)

fingerprintco-occurrences
4:47+17:0:1240:65535,9:mss,sok,ts,nop,ws:df,id+:01
4:58+6:0:1240:65535,9:mss,sok,ts,nop,ws:df,id+:01
4:44+20:0:1240:65535,9:mss,sok,ts,nop,ws:df,id+:01
4:112+16:0:1240:65535,9:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Mobile Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.361
Harmonic-HN-Android/3.0.1/release1
Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Mobile Safari/537.361

Country

fingerprintco-occurrences
US · United States1
FI · Finland1
TR · Turkey1
AL · Albania1

Network (ASN)

fingerprintco-occurrences
AS15169 · Google LLC1
AS39351 · 31173 Services AB1
AS197706 · Keminet SHPK1
AS15897 · Vodafone Telekomunikasyon A.S.1

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
q13d0311h3_55b375c5d22e_653d80c3fe9d2