Autonomous System

AS204666 Jiri Tlapak

ISPActiveCzechiaRIPE

AS204666 (TLAPNET-CZ) is an ISP network operated by Jiri Tlapak in Czechia, registered with RIPE. It has 38 IPv4 prefixes with 20,736 addresses and 11 IPv6 prefixes, which makes it the 6,727th largest of 82,200 active autonomous systems by IPv4 space.

IPv4 addresses20,736in 38 prefixes
IPv6 prefixes11≈ 5.8 × 10³⁰ addresses
Size rank#6,727of 82,200 active ASNs
Abuser scoreElevated0.86% of its addresses flagged · method

Details

OrganizationJiri Tlapak
AS nameTLAPNET-CZ
Websitetlapnet.cz
Country Czechia (CZ)
Network typeISP
RegistryRIPE
Abuse contactzneuziti@tlapnet.cz
Registered2018-01-29
Last updated2026-08-17

IPv4 prefixes

38 prefixes · 20,736 addresses
NetworkAddressesFirst – last address
37.221.240.0/204,09637.221.240.0 – 37.221.255.255
45.153.192.0/221,02445.153.192.0 – 45.153.195.255
85.255.88.0/221,02485.255.88.0 – 85.255.91.255
185.19.0.0/221,024185.19.0.0 – 185.19.3.255
185.64.220.0/221,024185.64.220.0 – 185.64.223.255
185.87.140.0/221,024185.87.140.0 – 185.87.143.255
185.97.24.0/221,024185.97.24.0 – 185.97.27.255
185.230.172.0/221,024185.230.172.0 – 185.230.175.255
185.243.172.0/221,024185.243.172.0 – 185.243.175.255
5.59.102.0/235125.59.102.0 – 5.59.103.255
91.224.90.0/2351291.224.90.0 – 91.224.91.255
185.87.142.0/23512185.87.142.0 – 185.87.143.255
213.108.162.0/23512213.108.162.0 – 213.108.163.255
37.221.241.0/2425637.221.241.0 – 37.221.241.255
37.221.242.0/2425637.221.242.0 – 37.221.242.255
37.221.243.0/2425637.221.243.0 – 37.221.243.255
37.221.245.0/2425637.221.245.0 – 37.221.245.255
37.221.247.0/2425637.221.247.0 – 37.221.247.255
37.221.248.0/2425637.221.248.0 – 37.221.248.255
37.221.249.0/2425637.221.249.0 – 37.221.249.255
37.221.250.0/2425637.221.250.0 – 37.221.250.255
37.221.251.0/2425637.221.251.0 – 37.221.251.255
37.221.252.0/2425637.221.252.0 – 37.221.252.255
45.153.192.0/2425645.153.192.0 – 45.153.192.255
45.153.194.0/2425645.153.194.0 – 45.153.194.255
The 25 largest of 38. The API and the database have all of them.

IPv6 prefixes

11 prefixes
  • 2a04:c740::/29
  • 2a04:f940::/29
  • 2a05:aa00::/29
  • 2a06:400::/29
  • 2a0a:10c0::/29
  • 2a0d:1880::/29
  • 2a0d:3140::/29
  • 2a0f:9300::/29
  • 2a0f:fec0::/29
  • 2a03:d840::/32
  • 2a03:d840:fe02::/48

Query AS204666 with the API

The ASN lookup returns everything on this page as JSON, including every prefix. ASN lookups need an API key: a free account comes with 1,000 requests a day. 

curl "https://api.ipapi.is/?q=AS204666&key=YOUR_API_KEY"

Any address in its prefixes resolves to AS204666, with or without a key:

curl "https://api.ipapi.is/?q=37.221.240.1"

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