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ASN Lookup

Find the Autonomous System (AS) that originates any public IP address.

How to read the result

Every public IP is announced on the global BGP routing table by an Autonomous System. This lookup queries Team Cymru's IP-to-ASN service and returns the origin ASN, the announcing prefix, and the registry country.

Example

8.8.8.8 → AS15169 (Google), 8.8.8.0/24, US

FAQ

What is an ASN?

An Autonomous System Number identifies a network operator (e.g. AS15169 = Google) that announces IP prefixes via BGP.

Why no result?

Private and reserved IPs (10.x, 192.168.x, 127.x) are never announced on the public internet, so they have no ASN record.

Where does the data come from?

Live DNS queries to Team Cymru's origin service — the same source many network operators use.