TCP SYN (JA4T)

42340_2-4-8-1-3_1400_9

first seen 2026-09-14 12:50 · last seen 2026-10-28 07:27 · JSON

Last 7 days (1 observations)

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 window42340
Option kinds2-4-8-1-3
MSS1400
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
t13d521100_b262b3658495_8e6e362c5eac2
t13d311100_e8f1e7e78f70_d41ae481755e Match?Exact match in Thumbprint's published controlled catalog captures: rust-hyper 1.11.1, rust-hyper 1.11.0, rust-hyper 1.12.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d3013h2_1d37bd780c83_8537cf56674e1
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, +28 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn07enus_71b742b5154a_000000000000_0000000000002
ge20nn13enus_0c2c1d640f3e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 151.0.7922.137, chrome 151.0.7922.170, chrome 151.0.7922.108, +36 more.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn050000_ea6f06182064_000000000000_0000000000001
ge20nn030000_bf75ddd0bb29_000000000000_0000000000001

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.1
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +57 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
4:48+16:0:1400:mss*29,9:mss,sok,ts,nop,ws:df,id+:02
4:49+15:0:1400:mss*29,9:mss,sok,ts,nop,ws:df,id+:02
4:46+18:0:1400:mss*29,9:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (compatible; The Lounge IRC Client; +https://github.com/thelounge/thelounge) facebookexternalhit/1.1 Twitterbot/1.02
curl/8.14.11
Mozilla/5.0 (Linux; Android 11; V2156A Build/RP1A.200720.012; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/129.0.6668.54 Mobile Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 Chrome/140.0.0.0 Safari/537.361

Country

fingerprintco-occurrences
US · United States2
CN · China1
EE · Estonia1
FI · Finland1

Network (ASN)

fingerprintco-occurrences
AS16591 · Google Fiber Inc.2
AS4134 · CHINANET BACKBONE1
AS218731 · Andris Jakovlevs1
AS213702 · QWINS LTD1

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.2