Autonomous systems & prefixes
Which network owns this IP? The ASN Lookup shows organization, country and all announced IPv4/IPv6 prefixes for any AS number. Essential for network admins, abuse handling and routing analysis.
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Look up any Autonomous System number to find the organization, country, and announced IP prefixes. Powered by RIPEstat.
How it works
1. Enter ASN
Enter an AS number (e.g. AS3320) – or start from an IP.
2. Load data
Organization, country and prefixes are loaded.
3. Analyze
Browse prefixes, check IPs, identify network operators.
Features in detail
ASN information
Organization, country and registrar for every AS number.
Prefix lists
All announced IPv4 and IPv6 prefixes at a glance.
IP → ASN
Jump from an IP directly to its associated AS.
RIPEstat data
Data from RIPE NCC – worldwide and always up to date.
Abuse analysis
For abuse reports: quickly identify the network operator of an attacker IP.
No account needed
Free and without registration.
Frequently asked questions
What is an ASN (Autonomous System)?
An Autonomous System is a network or group of networks under one administration with its own routing policy — e.g. Hetzner (AS24940) or Google (AS15169). The ASN is its globally unique number.
Who owns an IP address?
Every public IP is assigned to an RIR (RIPE, ARIN, APNIC...) which distributes it to provider networks (ASNs). The ASN lookup shows operator, prefixes and registration data — down to the abuse contact.
What is the difference between IP lookup and ASN lookup?
The IP lookup answers: where is this single IP? The ASN lookup answers: which network is behind it — with all associated prefixes and peerings.
How do I find the hosting provider of an IP?
Enter the IP in the ASN lookup — you get ASN, operator name, country and all network prefixes. In case of abuse, the shown abuse contact is your path.
What is an autonomous system (AS)?
An AS is a network or group of networks under unified administration – e.g. an ISP or data center operator – with its own routing policy and unique AS number.
How do I find the ASN for an IP?
Use the IP Lookup first – the ASN is linked there and leads directly into the ASN Lookup.
Where does the data come from?
From official RIPE NCC data (RIPEstat) – the regional internet registry for Europe.