TCP SYN (JA4T)

65535_2-1-3-1-1-8-4-0-0_1376_6

first seen 2026-07-02 10:04 · last seen 2026-10-28 13:22 · JSON

Last 7 days (2 observations)

Distinct clients per day (last 30 days, peak 2/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 kinds2-1-3-1-1-8-4-0-0
MSS1376
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
t13d1713h1_ab0a1bf427ad_89ab6efea77318
t13d1518h2_8daaf6152771_4980c97edce010
t13d1516h2_8daaf6152771_d8a2da3f94cd Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.4
t13d4907h2_0d8feac7bc37_7395dae3b2f3 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.2
t13d1516h1_8daaf6152771_5b37b36a67c01

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn050000_ea6f06182064_000000000000_00000000000016
ge20nr12engb_54b4638ab28b_000000000000_0000000000008
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.4
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn040000_5b1e8b5f4d2d_000000000000_0000000000001
ge20nr13engb_0c2c1d640f3e_000000000000_0000000000001
ge11nn06enus_98e697c2fa06_000000000000_0000000000001
ge20nn03enus_dc308f3700d9_000000000000_0000000000001
ge20nn13engb_0c2c1d640f3e_000000000000_0000000000001
ge11nr16enus_5d9bbf25535b_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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 152.0.7977.83, +81 more.The fingerprint page shows the full measured match list. More on the catalog.7
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.6
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.2
1:65536;2:0;4:6291456;6:262144|15663105|3:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 151.0.7922.34, chromium 147.0.7727.15, chromium 145.0.7632.6, +26 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
6:54+10:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:flow:020
6:53+11:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:ecn,flow:05
6:45+19:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:flow:04
6:53+11:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:flow:03
6:53+11:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:ecn:01
6:56+8:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:ecn,flow:01
6:50+14:0:1376:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:ecn,flow:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124 Safari/537.3616
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.369
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.364
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/156.0.0.0 Safari/537.362
Mozilla/5.0 (Macintosh; Intel Mac OS X 14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 Chrome/124 Safari/5371
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 Chrome/124.0 Safari/537.361

Country

fingerprintco-occurrences
US · United States25
AU · Australia10

Network (ASN)

fingerprintco-occurrences
AS21928 · T-Mobile USA, Inc.25
AS1221 · Telstra Limited10

TLS supported groups

fingerprintco-occurrences
0a0a,11ec,001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 155.0.8059.40, chrome 156.0.8078.73, chromium 156.0.8078.47, +8 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.1

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
q13d0313h3_55b375c5d22e_eb028bd37c088
q13d0312h3_55b375c5d22e_178839b6cec11