Public vs private IP addresses: what an IP lookup shows

A public IP identifies an Internet-facing connection. A private IP identifies an address inside a local network. They answer different questions, so a lookup should explain which kind you entered.

Your device and your Internet connection

A phone or laptop on home Wi-Fi often has a private IPv4 address, such as one beginning with 192.168. Multiple devices can share one public IPv4 address through their router. A provider can also use shared address space before traffic reaches the Internet. IPv6 supports a different addressing model; a connection can expose public IPv6 as well as IPv4.

Find the public address

Open My IP to request the Internet-facing addresses seen by the detection service. The IPv4 and IPv6 paths are checked separately. If there is no IPv6 response, it means that check did not return an address; it does not by itself diagnose every part of your IPv6 configuration.

Inspect another address

The IP lookup accepts IPv4 and IPv6. Public addresses can return a network operator, ASN and approximate location. Private, loopback, link-local and reserved addresses are classified locally. They do not have a useful public city or ISP to look up.

Location describes a network estimate

A city in an IP database can reflect a provider gateway, routing arrangement or database estimate. It is not a street address, GPS reading or proof of who used a connection. Mobile networks, VPNs and shared infrastructure make that distinction especially useful.

Compare like with like

When checking a VPN, compare the address shown before and after connecting and note whether you are looking at IPv4 or IPv6. A browser may use a proxy for web requests while another networking feature uses a different route. The WebRTC test and DNS test inspect those particular workflows.

Addressing references: RFC 1918 and IANA special-purpose IPv4 registry.