Identity
A network number
An ASN identifies a routing domain, not a single device. One ASN can announce many IP ranges.
What is an ASN?
An ASN, or autonomous system number, identifies a network or group of networks that share a routing policy on the internet. ASN lookup helps connect IP addresses to network operators such as ISPs, hosting providers, cloud platforms, and large organizations.
Ownership
IP to organization
ASN data helps identify the ISP, hosting provider, cloud platform, or organization behind an IP address.
Routing
Internet paths
Networks use ASNs to exchange routing information and announce which IP ranges they can reach.
How ASN lookup works
Public internet routing is organized around autonomous systems. Each autonomous system has a number, and that number is used to identify the network in routing data. When an IP address belongs to a routed block, ASN lookup can help reveal which network announces or operates that block.
This is useful when you want to understand traffic sources, distinguish hosting providers from residential networks, analyze crawler traffic, or connect an IP address to a network owner.
ASN data is strongest when combined with IP geolocation and CIDR range analysis. The ASN gives network context, the geolocation data gives location signals, and the CIDR block gives the range boundaries.
FAQ
ASN questions
What does ASN mean?
ASN means autonomous system number, an identifier for a routed internet network.
What does ASN lookup show?
It can show the network number, organization name, country signals, and associated IPv4 ranges.
Is ASN an IP address?
No. An IP address identifies an address; an ASN identifies a network or routing domain.