ASN Lookup

Free online ASN Lookup. No sign-up needed, and it runs in your browser.

Find the network (ASN) behind an IP address or domain — owner, country and IP range — or look up an AS number.

Uses Team Cymru’s free IP-to-ASN service.

How to use

  1. Add your text or file.
  2. Adjust the options if needed.
  3. Copy or download the result.