What is an ASN, how BGP routing relates to IP lookup results, and why security teams track autonomous systems during fraud checks.
An Autonomous System Number (ASN) identifies a network that speaks BGP on the internet — typically an ISP, cloud provider, university, or enterprise. Format: AS15169 (Google), AS13335 (Cloudflare).
PINIP.net returns ASN, AS name, and CIDR prefix alongside geolocation for every lookup.
IP blocks move between ISPs after acquisitions. Country may stay stable while ASN changes. Fraud systems often block entire ASNs associated with bulletproof hosting or VPN exit nodes.
Team Cymru and RIPE data power our BGP prefix fields — visible on reports like 8.8.8.8.
Related but not identical. One ISP may operate several ASNs; one ASN may host many downstream brands.
Every IP report includes ASN under Network & ISP. Try 1.1.1.1 for Cloudflare AS13335.