ASN Lookup
Find the organization, routing footprint, route validity, and peering context behind an autonomous system number.
What this checks
- Registry owner, handle, country, registration dates, and public abuse or contact fields when RDAP returns them.
- Originated IPv4 and IPv6 prefixes from RouteViews with RPKI authorization status and representative base-IP lookup links.
- PeeringDB network profile, exchange presence, adjacent ASNs, optional Cloudflare Radar details, and representative IP risk samples.
How to interpret results
- A large prefix inventory usually indicates an ISP, cloud, CDN, enterprise backbone, or hosting provider rather than a single website.
- Invalid or not-found RPKI entries deserve routing review before trusting traffic sourced from that network.
- PeeringDB, adjacent ASN, and representative IP intelligence help distinguish consumer ISPs, hosting networks, VPN/proxy providers, and cloud infrastructure.
Common issues
- Some ASNs have limited RDAP, PeeringDB, RouteViews, or Radar coverage, so individual sections can be partial while others still load.
- Representative IP samples are selected from announced prefixes and should be treated as examples, not a complete scan of every address in the ASN.
Privacy note
ASN lookups run server-side against public routing and registry sources. The entered ASN is used to serve the request and is not meant to create a user profile.
Key Tools and References
Frequently Asked Questions
What does an ASN lookup show?
It identifies the organization behind an Autonomous System Number and summarizes registry ownership, announced prefixes, RPKI status, peering data, related ASNs, and representative IP intelligence.
Can I enter AS15169 or only 15169?
Both formats are accepted. The lookup normalizes an optional AS prefix before querying the ASN intelligence backend.