TCP SYN (p0f)

4:51+13:0:1460:mss*44,8:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-20 14:48 · last seen 2026-09-08 08:48 · JSON

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

IP version4
Initial TTL51+13
Options length0
MSS1460
Window sizemss*44
Window scale8
Options layoutmss,sok,ts,nop,ws
Quirksdf,id+
Payload class0

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_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.7
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.5
t13d1715h2_5b57614c22b0_a54fffd0eb613
t13d1515h1_8daaf6152771_0a20fe35d3a52
t13d491200_bd868743f55c_7c76daad20ec1
t13d1313h2_f57a46bbacb6_7f0f34a4126d1
t13d2812h2_a01be8c064b6_0d46a1bf4a7c1
t13d1515h1_8daaf6152771_de4a06bb82e31

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr12enus_54b4638ab28b_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 151.0.7922.137, edge 151.0.4129.93, +36 more.The fingerprint page shows the full measured match list. More on the catalog.5
ge20nr13itit_5907f7c6644a_000000000000_0000000000003
ge11nn13enus_9db22d02e17a_000000000000_0000000000003
ge20nr13enus_54728652be35_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, edge 149.0.4022.52, +10 more.The fingerprint page shows the full measured match list. More on the catalog.2
ge20nr12enus_a4e537ffe33a_000000000000_0000000000002
ge20nr15enus_69c8774e1c1b_000000000000_0000000000001
ge20nr13enus_47bedc02e943_000000000000_0000000000001
ge11nn050000_7d5093fcb167_000000000000_0000000000001
ge20nn07enus_0cf68805773e_000000000000_0000000000001
ge20nr14itit_3fb598f484fb_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 149.0.7827.102, +59 more.The fingerprint page shows the full measured match list. More on the catalog.6
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.3
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.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, +21 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
2:0;4:2097152;3:100;9:1|10485760|0|m,s,p,a1
1:65536;2:0;4:6291456;6:262144|15663105|5:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 133.0.6943.16, chrome 150.0.7871.128, chromium 148.0.7778.96, +2 more.The fingerprint page shows the full measured match list. More on the catalog.1
1:4096;2:0;4:2147483647;5:131072;8:0;3:100;6:65536|2147418112|0|m,s,p,a1

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_814

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0 Safari/537.366
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.0.0 Safari/537.364
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.03
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36 Edg/149.0.0.03
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/110.0.0.0 Safari/537.361
Mozilla/5.0 (compatible; Barkrowler/0.9; +https://babbar.tech/crawler)1
Hydra/21 CFNetwork/3860.600.12 Darwin/25.5.01

Country

fingerprintco-occurrences
US · United States8
IT · Italy4
NO · Norway3
SG · Singapore3
NL · Netherlands1
GB · United Kingdom1
FR · France1

Network (ASN)

fingerprintco-occurrences
AS208172 · Proton AG9
AS9009 · M247 Europe SRL6
AS56655 · Gigahost AS3
AS212238 · Datacamp Limited2
AS210743 · Babbar SAS1

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_653d80c3fe9d5