ASN Lookup by Domain Name
You can find the ASN for any domain by first resolving the domain to its IP address (via DNS), then looking up the ASN for that IP. This reveals which hosting provider, CDN, or cloud platform serves the domain.
How It Works
WarpCheck ASN Lookup accepts domain names directly. Internally, the tool resolves the domain using DNS to find its A (IPv4) or AAAA (IPv6) record, then queries the ASN database for the resolved IP. The result shows the ASN, network operator, and BGP prefix that covers the domain's IP address.
Why It Matters
Knowing a domain's ASN helps you understand its infrastructure: is it hosted on AWS, Cloudflare, Google Cloud, or a regional ISP? This is useful for competitive analysis, security research, CDN identification, and investigating shared hosting relationships.
Common Issues
- CDN domains resolve to different IPs per region — the ASN may vary based on geographic location
- Domains behind Cloudflare show Cloudflare's ASN (AS13335) rather than the origin server ASN
- Wildcard DNS or load balancers may show different ASNs on repeated lookups