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
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| Network | Addresses | First – last address |
|---|---|---|
| 37.221.240.0/20 | 4,096 | 37.221.240.0 – 37.221.255.255 |
| 45.153.192.0/22 | 1,024 | 45.153.192.0 – 45.153.195.255 |
| 85.255.88.0/22 | 1,024 | 85.255.88.0 – 85.255.91.255 |
| 185.19.0.0/22 | 1,024 | 185.19.0.0 – 185.19.3.255 |
| 185.64.220.0/22 | 1,024 | 185.64.220.0 – 185.64.223.255 |
| 185.87.140.0/22 | 1,024 | 185.87.140.0 – 185.87.143.255 |
| 185.97.24.0/22 | 1,024 | 185.97.24.0 – 185.97.27.255 |
| 185.230.172.0/22 | 1,024 | 185.230.172.0 – 185.230.175.255 |
| 185.243.172.0/22 | 1,024 | 185.243.172.0 – 185.243.175.255 |
| 5.59.102.0/23 | 512 | 5.59.102.0 – 5.59.103.255 |
| 91.224.90.0/23 | 512 | 91.224.90.0 – 91.224.91.255 |
| 185.87.142.0/23 | 512 | 185.87.142.0 – 185.87.143.255 |
| 213.108.162.0/23 | 512 | 213.108.162.0 – 213.108.163.255 |
| 37.221.241.0/24 | 256 | 37.221.241.0 – 37.221.241.255 |
| 37.221.242.0/24 | 256 | 37.221.242.0 – 37.221.242.255 |
| 37.221.243.0/24 | 256 | 37.221.243.0 – 37.221.243.255 |
| 37.221.245.0/24 | 256 | 37.221.245.0 – 37.221.245.255 |
| 37.221.247.0/24 | 256 | 37.221.247.0 – 37.221.247.255 |
| 37.221.248.0/24 | 256 | 37.221.248.0 – 37.221.248.255 |
| 37.221.249.0/24 | 256 | 37.221.249.0 – 37.221.249.255 |
| 37.221.250.0/24 | 256 | 37.221.250.0 – 37.221.250.255 |
| 37.221.251.0/24 | 256 | 37.221.251.0 – 37.221.251.255 |
| 37.221.252.0/24 | 256 | 37.221.252.0 – 37.221.252.255 |
| 45.153.192.0/24 | 256 | 45.153.192.0 – 45.153.192.255 |
| 45.153.194.0/24 | 256 | 45.153.194.0 – 45.153.194.255 |
37.221.240.0/20 45.153.192.0/22 85.255.88.0/22 185.19.0.0/22 185.64.220.0/22 185.87.140.0/22 185.97.24.0/22 185.230.172.0/22 185.243.172.0/22 5.59.102.0/23 91.224.90.0/23 185.87.142.0/23 213.108.162.0/23 37.221.241.0/24 37.221.242.0/24 37.221.243.0/24 37.221.245.0/24 37.221.247.0/24 37.221.248.0/24 37.221.249.0/24 37.221.250.0/24 37.221.251.0/24 37.221.252.0/24 45.153.192.0/24 45.153.194.0/24
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
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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