Look up an autonomous system number (ASN) to see the network name, organization, country, registration dates and abuse contact from its registry.
About this tool
Look up an autonomous system number (ASN) to see who owns it and its registration details.
How to use ASN WHOIS Lookup
- Enter an AS number with or without the AS prefix, such as AS13335.
- Click Look up ASN.
- Review the organization and contacts in the registry record.
Worked example
AS15169 returns GOOGLE, registered to Google LLC with ARIN. You will often find ASNs in IP location results, BGP tools and firewall logs.
What is an ASN?
An autonomous system number identifies a network that controls its own routing on the internet, such as an ISP, cloud provider or large company.
Where do I find an IP address’s ASN?
The IP location lookup shows the ASN of any IP address, which you can then look up here.
- ASN WHOIS Lookup — Look up an autonomous system number (ASN) to see who owns it and its registration details.
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