TCP SYN (JA4T)

42340_2-4-8-1-3_1363_11

first seen 2026-10-23 21:45 · last seen 2026-10-23 22:42 · JSON

Distinct clients per day (last 30 days, peak 81/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 window42340
Option kinds2-4-8-1-3
MSS1363
Window scale11

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_8537cf56674e82

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_00000000000082

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.82

TCP SYN (p0f)

fingerprintco-occurrences
4:115+13:0:1363:mss*29,11:mss,sok,ts,nop,ws::023
4:116+12:0:1363:mss*29,11:mss,sok,ts,nop,ws::017
4:111+17:0:1363:mss*29,11:mss,sok,ts,nop,ws::010
4:114+14:0:1363:mss*29,11:mss,sok,ts,nop,ws::08
4:113+15:0:1363:mss*29,11:mss,sok,ts,nop,ws::05
4:105+23:0:1363:mss*29,11:mss,sok,ts,nop,ws::05
4:110+18:0:1363:mss*29,11:mss,sok,ts,nop,ws::04
4:108+20:0:1363:mss*29,11:mss,sok,ts,nop,ws::02
4:107+21:0:1363:mss*29,11:mss,sok,ts,nop,ws::02
4:118+10:0:1363:mss*29,11:mss,sok,ts,nop,ws::01

User-Agent

fingerprintco-occurrences
curl/8.14.182

Country

fingerprintco-occurrences
JP · Japan40
KR · South Korea31
US · United States4
VN · Vietnam2
CA · Canada1
GB · United Kingdom1
MX · Mexico1
IN · India1
MY · Malaysia1

Network (ASN)

fingerprintco-occurrences
AS4766 · Korea Telecom26
AS2516 · KDDI CORPORATION10
AS17676 · SoftBank Corp.9
AS4713 · NTT DOCOMO BUSINESS,Inc.6
AS2527 · Sony Network Communications Inc.4
AS17858 · LG POWERCOMM3
AS18403 · FPT Telecom Company2
AS18126 · Chubu Telecommunications Company, Inc.2
AS17511 · OPTAGE Inc.2
AS7922 · Comcast Cable Communications, LLC1

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.82