ASN Lookup Tool
Look up Autonomous System Number (ASN) details and associated IP blocks with our free ASN lookup tool.
Enter ASN Number
What is an ASN? An Autonomous System Number (ASN) is a unique identifier assigned to a network or group of networks that maintain a cohesive routing policy. Each ASN is controlled by a single organization, like an Internet Service Provider (ISP), university, or large company. ASNs are fundamental to BGP (Border Gateway Protocol), which is the routing protocol that makes the Internet work.
ASN Lookup Tool Guide
Our comprehensive ASN lookup tool allows you to find detailed information about Autonomous System Numbers (ASNs) and the networks they represent.
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