ASN Lookup & Prefix List
Lookup Autonomous System Numbers (ASN), IP prefixes, and network ownership details.
Lookup Autonomous System Numbers (ASN) and IP prefixes to discover network ownership, geographical location, and registration dates using real-time RDAP and WHOIS intelligence.
How it works
Our tool integrates with official Regional Internet Registries (RIRs) via the RDAP (Registration Data Access Protocol) and leverages DNS-based BGP mapping to resolve IP addresses to their corresponding AS numbers instantly.
Frequently asked questions
What is an ASN?
An Autonomous System Number (ASN) uniquely identifies a network on the internet that has a clearly defined routing policy (BGP).
Can I search by IP address?
Yes, you can enter any IPv4 or IPv6 address. The tool will resolve its routing prefix and fetch the corresponding ASN.
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