TCP SYN (JA4T)

64240_2-4-8-1-3_1320_8

first seen 2026-10-23 22:26 · last seen 2026-10-23 22:32 · 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 window64240
Option kinds2-4-8-1-3
MSS1320
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_8537cf56674e3

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_0000000000003

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.3

TCP SYN (p0f)

fingerprintco-occurrences
4:51+13:0:1320:mss*44,8:mss,sok,ts,nop,ws:df,id+:01
4:47+17:0:1320:mss*44,8:mss,sok,ts,nop,ws:df,id+:01
4:41+23:0:1320:mss*44,8:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
curl/8.14.13

Country

fingerprintco-occurrences
NL · Netherlands1
FR · France1
FI · Finland1

Network (ASN)

fingerprintco-occurrences
AS203273 · NetCrafters OU2
AS210644 · AEZA GROUP 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.3