# WebRTC leak test and timezone check
> What this site can show about a VPN, and why it is not a DNS leak test.
The server sees one address. The browser may also reveal candidates through WebRTC, and it has its own timezone. This page compares those. A 10.x, 192.168.x, or 100.64.x address is your network or CGNAT, not a leak by itself.

This is not a DNS leak test. That test has to observe the resolver. See [what a DNS leak test checks](https://ipinfo.fyi/guides/dns-leak) and the [WebRTC page](https://ipinfo.fyi/tools/webrtc-leak).

The ASN list is short. A clear result does not prove the absence of a VPN.
## Questions

### What is a WebRTC leak test?

WebRTC gathers possible network paths for a call. A leak is a second public address, gathered by the browser, that is not the address this site already saw. The test on this site runs only after you click.

### What is a DNS leak test?

A DNS leak is when name lookups go to a resolver outside the VPN. This site does not run that test, because it would need to see which resolver asked for a name. The guide explains what to look for.

### Does a timezone mismatch prove a VPN?

No. The browser timezone comes from the operating system. The IP timezone comes from a geolocation database. They also differ when you travel or when the database is wrong.