TCP SYN (JA4T)

65535_2-4-8-1-3_1388_6

first seen 2026-07-21 12:01 · last seen 2026-09-10 02:56 · JSON

Last 7 days (3 observations)

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 window65535
Option kinds2-4-8-1-3
MSS1388
Window scale6

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
t13d3112h2_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.5.0, php-curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.15
t13d1515h1_8daaf6152771_de4a06bb82e36
t13d1515h1_8daaf6152771_0a20fe35d3a55
t13d4412h1_fd39b124ee10_58ed7828516f3
t13d1517h2_8daaf6152771_b1ff8ab2d16f1

HTTP request (JA4H)

fingerprintco-occurrences
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.15
ge11nn13enus_9db22d02e17a_000000000000_00000000000010
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.3
ge20nr13enus_e2ac93ffb364_000000000000_0000000000001
ge11nn14enus_4a2973d235de_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
3:100;4:10485760;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0.The fingerprint page shows the full measured match list. More on the catalog.15
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
4:44+20:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:010
4:43+21:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:05
4:46+18:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:04
4:48+16:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:03
4:47+17:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:03
4:49+15:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:02
4:45+19:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:01
4:51+13:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:01
4:236+19:0:1388:65535,6:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
curl/8.5.015
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.362
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.362
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.75 Safari/537.362
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.361
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/120.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/101.0.4951.67 Safari/537.361

Country

fingerprintco-occurrences
US · United States23
BR · Brazil2
AZ · Azerbaijan2
PH · Philippines1
UY · Uruguay1
DO · Dominican Republic1

Network (ASN)

fingerprintco-occurrences
AS6167 · Verizon Business22
AS272436 · TERCIO FELIPE LOURENCO PEREIRA2
AS196961 · Teleport LLC2
AS21928 · T-Mobile USA, Inc.1
AS6057 · Administracion Nacional de Telecomunicaciones1
AS6400 · Compañía Dominicana de Teléfonos S. A.1
AS4775 · Globe Telecoms1