What the internet can see about you

Reading

Reading every channel that identifies you.

Can we find you?

The address that reaches us names a place. But the round-trip time alone fixes how far you sit from this instrument, by the speed of light in fiber - no database needed. We fuse the two and report a best guess with its odds, never a false certainty.

The road to your door

Distance is one reading. The other is the route itself: every network that carries packets from this server to you, in order, and how long each leg takes. Anyone on that path can see that you and this server are talking.

Is the network lying to you?

Some special packets carry a request to be stamped by every router they pass. It is a way to see the path the network normally hides. But many ISP edges intercept those packets and answer them with a forged reply, impersonating the destination. This sends a plain packet and a special one to the same known hosts and compares the answers - if they disagree, a device on your line is faking replies for the rest of the internet.

What this checks

IPv4 route. The address that actually arrived here - what any site you visit sees as you, and the network that owns it. If you route through a VPN or tunnel, this is its exit rather than you.

IPv6 route. Many devices also reach the internet over IPv6, a separate address that identifies you just as well. This check contacts an outside IPv6-only address, because proving IPv6 works at all requires something outside to answer.

Browser. Browsers can hand your real address to any page through WebRTC, no matter how your traffic is routed.

DNS resolver. Not tested yet. Testing it needs this server to answer DNS queries directly, which collides with the ad-blocking resolver already running here. Listed so it reads as untested rather than passing.