IP to ASN
Finds the autonomous system number for an IP address or domain; by AS number it shows the owner, all address blocks and neighboring networks.
An autonomous system is a network under one operator: an ISP, a hosting provider, or a large company. Each one has a number, an ASN, and that number tells you whose network is responsible for an address.
Lookup by AS number
Enter a number, AS8359 for example, and get all the address blocks the network announces on the internet. You can copy the full list at once, for example to use it in firewall rules.
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