ASN Info API
An autonomous system (AS) is a collection of connected Internet Protocol (IP) routing prefixes managed by one or more network operators on behalf of a single administrative entity or domain. It has a single and clearly defined external routing policy.
An autonomous system number (ASN) is a unique number used to identify an autonomous system. It enables that system to exchange exterior routing information with other neighbouring autonomous systems.
A detailed two-part blog post that explains the fundamentals of these systems and the role of AS is available below:
The AS Info APIs provide valuable information about the autonomous systems which allows you to identify the ownership of the systems and discover their neighbouring systems.
This API returns extended and detailed information about an Autonomous System (AS) when provided with an AS number. The information includes the registration, IPv4 address space announcements and ranking.
This API is part of the IP Geolocation package and is available in free and paid plans. Please visit the IP Geolocation package page for limits and pricing information.
https://api.bigdatacloud.net/data/asn-info?asn=AS7545&localityLanguage=en&key=[YOUR API KEY]