TCP SYN (JA4T)

65535_2-1-3_1460_8

first seen 2026-09-02 18:03 · last seen 2026-10-23 22:45 · JSON

Distinct clients per day (last 30 days, peak 230/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 kinds2-1-3
MSS1460
Window scale8

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
t13d3013h2_1d37bd780c83_8537cf56674e234
t13d4312h1_c7886603b240_b26ce05bbdd61
t13d1515h1_8daaf6152771_0a20fe35d3a51
t13d1515h1_8daaf6152771_de4a06bb82e31

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_000000000000234
ge11nn13enus_9db22d02e17a_000000000000_0000000000002
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.1

HTTP/2 frames (Akamai)

fingerprintco-occurrences
3:100;4:65536;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, curl 8.18.0, curl 8.21.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.234

TCP SYN (p0f)

fingerprintco-occurrences
4:47+17:0:1460:65535,8:mss,nop,ws::058
4:43+21:0:1460:65535,8:mss,nop,ws::035
4:44+20:0:1460:65535,8:mss,nop,ws::030
4:46+18:0:1460:65535,8:mss,nop,ws::025
4:57+7:0:1460:65535,8:mss,nop,ws::023
4:53+11:0:1460:65535,8:mss,nop,ws::020
4:56+8:0:1460:65535,8:mss,nop,ws::013
4:55+9:0:1460:65535,8:mss,nop,ws::010
4:45+19:0:1460:65535,8:mss,nop,ws::05
4:52+12:0:1460:65535,8:mss,nop,ws::05

User-Agent

fingerprintco-occurrences
curl/8.14.1234
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 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 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

Country

fingerprintco-occurrences
NL · Netherlands81
US · United States54
DE · Germany51
FR · France17
JP · Japan12
GB · United Kingdom11
CA · Canada6
BG · Bulgaria2
TR · Turkey2
MX · Mexico1

Network (ASN)

fingerprintco-occurrences
AS12876 · Scaleway SAS83
AS16276 · OVH SAS81
AS63023 · GTHost27
AS40676 · Psychz Networks12
AS152194 · CTG Server Limited9
AS62563 · GLOBALTELEHOST Corp.6
AS20860 · IOMART CLOUD SERVICES LIMITED3
AS24961 · WIIT AG2
AS23470 · ReliableSite.Net LLC2
AS63018 · Dedicated.com2

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,001e,0018,0019,0100,0101 Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 24.22.1, python-httpx 0.28.1, python-requests 2.34.2, +2 more.The fingerprint page shows the full measured match list. More on the catalog.234