LOOKIP.IO

ASN Directory

78,261 Autonomous Systems distilled from our IP intelligence dataset. Browse the largest networks below, pick a country to walk the whole directory, or open any ASN page directly at /asn/<number>.

Top ASNs by IPv4 Space

The badge is how many IPv4 /24 blocks our directory attributes to each network. For the prefixes an AS is announcing right now, open its page.

Browse by Country

Every country in the directory, most networks first. The number is how many Autonomous Systems are registered there.

What's an ASN?

An Autonomous System Number identifies a single network on the internet — a company, ISP or cloud provider that announces a set of IP prefixes via BGP. When you look up an IP on Lookip, the ASN row tells you who's actually responsible for routing that address.