How the ISP is identified
Every public IP address is announced on the internet by an autonomous system (AS) — a network run by an ISP, hosting company or large organisation. The ISP shown here is the name registered for that network.
For your own connection, the network is read from how your traffic reaches Cloudflare. For another IP, we look up its origin ASN through Team Cymru's IP-to-ASN service and the registration record through RDAP, the registries' official lookup protocol.
Why the name may look unfamiliar
- Legal or parent company names — registries use company names (for example, a telecom's full legal name) rather than retail brands.
- Wholesale networks — some smaller providers resell capacity from a larger network, whose name appears instead.
- VPNs, relays and hosting — if you use a VPN or iCloud Private Relay, you'll see that operator.
When this is useful
- Confirming which provider a connection uses before calling support or filing a complaint.
- Checking whether a VPN is active.
- Identifying the network behind an IP address in server logs — pair it with IP lookup and reverse DNS.
Questions
What is an ASN?
An autonomous system number identifies a network that routes its own IP address blocks on the internet. Each ISP has at least one ASN; large ones have several.
Can this tell me which plan or technology I have?
No. The registry only identifies the network operator. Whether you're on fibre, DSL or 4G isn't recorded there — check with your provider or your router's status page.