IP BGP Lookup

Every public IP address is reachable on the internet via BGP routes announced by Autonomous Systems. When you look up an IP, you're querying the global routing table to find which AS "owns" that address block and how widely the route is propagated.

Understanding BGP Routing for an IP

• Longest Prefix Match: BGP routers use the most-specific (longest) matching prefix. An IP like 8.8.8.8 might match both 8.0.0.0/8 and 8.8.8.0/24 — the /24 wins.
• AS Path: The sequence of ASNs a packet traverses to reach its destination, used to detect loops and apply routing policy.
• RPKI Validity: Route Origin Authorization certificates cryptographically bind a prefix to its authorized origin ASN, preventing route hijacks.
• Peer Visibility: More route collector peers seeing a prefix means broader global propagation and higher confidence in the route.

Use Cases

Network engineers use IP BGP lookups to investigate suspicious traffic sources, verify that their own IP blocks are correctly announced, identify BGP hijacks in real-time, and research the network infrastructure behind any IP address.