What IP geolocation and speed tests actually tell you

Network lookup tools produce numbers that are easy to misread. Here is how to interpret the three most common ones.

IP geolocation is an estimate

A geolocation lookup combines registry data (who the block was assigned to) with routing and latency hints. Country-level results are nearly always right; city-level is usually right; street-level never is. Mobile and VPN addresses resolve to the provider's gateway city, not the user's — a London mobile user may show up in Manchester.

The ASN is the trustworthy field

The Autonomous System Number tells you which network announces the address, and routing does not lie about that. "Is this visitor really from ISP X?" is answerable; "are they in this postcode?" is not.

Why browser speed tests read low

A browser test moves data over a single HTTP connection. Multi-stream apps open several in parallel and can saturate a gigabit line; a single stream cannot. Expect roughly 60–80% of your plan speed in a browser — the number is honest, just bounded by the method.

Jitter matters more than speed for calls

A 20 Mbps line with 10 ms jitter carries video calls better than a 200 Mbps line with 80 ms jitter. If calls break up on a "fast" connection, jitter — not bandwidth — is the number to check.