TCP SYN (JA4T)

64440_2-4-8-1-3_1432_10

first seen 2026-07-01 15:07 · last seen 2026-09-07 13:25 · 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 window64440
Option kinds2-4-8-1-3
MSS1432
Window scale10

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_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.4
t13d1515h2_8daaf6152771_a54fffd0eb613
t12d290700_fc2078a0b8c0_8c06664c3ac52
t13d1514h2_8daaf6152771_53a6d0ab1c422
t13d3113h1_e8f1e7e78f70_d339722ba4af1
t13d3013h2_1d37bd780c83_8537cf56674e1
t13d1616h2_86a278354501_fe7c3632a08d1
t13d3513h2_bfa337485184_8d7351bd871b Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.18.0.The fingerprint page shows the full measured match list. More on the catalog.1
t13d5212h1_b262b3658495_8e6e362c5eac Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 24.19.0, node-fetch 22.23.1, node-fetch 24.21.0, +6 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr11enus_187a9385d229_000000000000_0000000000004
ge20nr14eses_a482706b3270_000000000000_0000000000002
ge11nn040000_bfa5a9b89dd6_000000000000_0000000000001
ge11nn030000_dd98166e0881_000000000000_0000000000001
ge11nn050000_f42f60d0fe7d_000000000000_0000000000001
ge20nr12enus_a72b71f519fc_000000000000_0000000000001
ge20nn030000_e057572924c3_000000000000_0000000000001
ge20nn14engb_f9d9734092dc_000000000000_0000000000001
ge20nr13engb_9e6b72014148_000000000000_0000000000001
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.18.0, +9 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 154.0, +25 more.The fingerprint page shows the full measured match list. More on the catalog.5
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.3
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, +7 more.The fingerprint page shows the full measured match list. More on the catalog.2
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:42|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 152.0.1, +3 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, +43 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
6:43+21:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:04
6:45+19:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:03
6:44+20:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:02
6:46+18:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:02
6:244+11:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:02
6:235+20:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:01
6:237+18:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:01
6:243+12:0:1432:mss*45,10:mss,sok,ts,nop,ws:flow:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (X11; Linux x86_64; rv:151.0) Gecko/20100101 Firefox/151.05
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.364
Mozilla/5.0 (compatible; MJ12bot/v1.4.8; http://mj12bot.com/)2
Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.01
Mozilla/5.0 (compatible; clatter.el)1
curl/8.18.01
vroni-job-signals/1.0 (+manual review)1
hn-build Bot/1.0 (+directory preview)1

Country

fingerprintco-occurrences
DE · Germany11
GB · United Kingdom2
ES · Spain2
JO · Jordan1

Network (ASN)

fingerprintco-occurrences
AS8881 · 1&1 Versatel GmbH5
AS3320 · Deutsche Telekom AG3
AS5378 · Vodafone Limited2
AS57269 · DIGI SPAIN TELECOM S.A2
AS15943 · wilhelm.tel GmbH2
AS8376 · Jordan Data Communications Company LLC1
AS12312 · ecotel communication ag1

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_653d80c3fe9d3
q13d0315h3_55b375c5d22e_dc5437974b471
q13d0315h3_55b375c5d22e_78345df32b3a1