Reverse ASN Lookup Tool
Shortcuts: / or Ctrl+L to focus, Esc to return
Frequently Asked Questions
- What is Reverse ASN Lookup?
- It finds IP ranges announced by a given ASN, helping understand network ownership and routing scope.
- How does Reverse ASN Lookup work?
- The tool queries ASN to prefix mappings and lists the associated CIDR ranges. Totals are computed from CIDR sizes.
- Why is Reverse ASN Lookup important for network security?
- Security teams, network operators, and researchers use it for attribution, allow and deny lists, and traffic analysis.
- Can I find all IPs for a specific ASN?
- The tool provides comprehensive listings of IP ranges associated with a given ASN.
- Are Reverse ASN Lookup results up to date?
- Results reflect the ASN mapping dataset currently available to this service. BGP announcements can change quickly, so treat this as a strong baseline and verify critical decisions with your upstream routing data.