IP to ASN (autonomous system number) is possible with IPinfo’s API, giving our customers access to a database that includes every ASN’s related domains, allocation date, registry name, total number of IP addresses, and assigned prefixes.

ISP lookup for IP addresses is available to IPinfo customers on our standard and pro plans. Our ASN API endpoint returns a JSON response with data for both IPv4 and IPv6 prefixes, including netblocks, IDs, names, and countries for networks and internet service providers.

Resolving the IP address to ASN for users that visit your website will provide your business with insight on which ISPs are common among your IP traffic. This data can help you make inferences about users’ internet connection speeds, data limitations, and so forth.

IPinfo offers the most reliable ASN lookup service on the web. Our proprietary network data sets are updated every day so that our ASN database is as accurate and complete as it gets.