An ASN (Autonomous System Number) is a unique number assigned to an Autonomous System (AS) organization that operates a collection of IP networks and routers. ASNs serve as identifiers for organizations or entities that own or operate networks and have been allocated IP address ranges by a regional Internet authority, such as a Regional Internet Registry (RIR).
In IPinfo’s case, instead of assigning a unique number, we generally prefix ASNs with “AS” for easier identification and data operations.