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Enter an ASN (e.g. AS13335) or IP address.
ASN Lookup
Look up ASN owner, announced IP prefixes, RIR, and abuse contact. Identify network infrastructure from ASN or IP.
Detected
Announced Prefixes
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Tool Features
Related Guides
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ASN / BGP Lookup
Look up any Autonomous System Number or IP address to identify the network operator, announced prefixes, RIR, country and abuse contact. The tool flags well-known cloud and hosting networks, plus education and government networks by name. Useful for threat intelligence, IP attribution and understanding the network behind an address.
How It Works
Data comes from RIPEstat: as-overview for the holder name, announced-prefixes for the prefixes, abuse-contact-finder for the abuse address, and its RIR and country datasets for the registry and country. For an IP address, the announcing ASN is looked up first with RIPEstat network-info. Networks are labelled from a list of known provider ASNs and name patterns.
FAQ
What is an ASN?
An Autonomous System Number (ASN) identifies a network operator on the internet. Each ASN manages a set of IP prefixes and participates in BGP routing. Examples: AS13335 (Cloudflare), AS15169 (Google), AS16509 (Amazon AWS). ASNs are assigned by Regional Internet Registries (ARIN, RIPE, APNIC, etc.).
How can I find which ASN owns an IP address?
Enter the IP address in this tool — it looks up the ASN that announces the address. From the command line you can use "whois -h whois.radb.net 1.2.3.4" or Team Cymru's DNS service: "dig +short TXT 4.3.2.1.origin.asn.cymru.com" for 1.2.3.4 (octets reversed).
What is an abuse contact and when should I use it?
The abuse contact is the email address designated for reporting malicious activity originating from that network. Use it to report spam, DDoS attacks, port scanning, or other abuse. Include timestamps, source IPs, and log evidence in your report.