ASN WHOIS Lookup

ASN assignment follows a two-tier system. IANA (Internet Assigned Numbers Authority) holds global authority over all Autonomous System Numbers and allocates them in blocks to five Regional Internet Registries (RIRs), which then assign individual ASNs to network operators and ISPs within their regions:

• ARIN : North America
• RIPE NCC : Europe, Russia & Middle East
• APNIC : Asia Pacific
• LACNIC : Latin America & Caribbean
• AFRINIC : Africa

The RIR responsible for any ASN you look up is shown directly in the WhoisFreaks ASN WHOIS lookup result.

• IP WHOIS identifies who owns a specific IP address : it returns the registered organisation, ISP, ASN, abuse contact, and the IP range that address belongs to. This data comes from official Regional Internet Registry records.
• ASN WHOIS goes one level up : it tells you about the autonomous system itself, the network entity that controls a group of IP ranges and announces them to the internet via BGP routing.
• An IP address belongs to a range, and that range is managed by an ASN. So an IP WHOIS result will show you the ASN, and an ASN WHOIS result will show you all the IP prefixes that autonomous system controls.
• Use IP WHOIS Lookup when you have a specific IP and want to know who is responsible for it. Use ASN WHOIS Lookup when you want to understand the full network infrastructure behind an organisation.