Question 1

What is a DNS leak?

Accepted Answer

A DNS leak is when your DNS lookups — the question "which IP is example.com?" — are answered by a server you did not choose, typically your ISP's resolver, even though your traffic is going through a VPN. Whoever answers can see every domain you visit next to your real IP address.

Question 2

How does this DNS leak test work?

Accepted Answer

Your browser looks up a series of one-off hostnames that exist only on our own DNS nameservers. Whichever DNS resolvers come asking for them are the resolvers your device really uses. We report their IP addresses, operator and country. We do not read your device settings and nothing is stored.

Question 3

Why do my DNS servers not match what I configured?

Accepted Answer

VPN apps usually override your device's DNS with their own resolvers, and some routers or networks intercept DNS. This test shows the servers that actually answered, which is what matters for privacy.

Question 4

How do I fix a DNS leak?

Accepted Answer

Turn on your VPN's DNS leak protection (often called block outside DNS or a kill switch), set your operating system's DNS to automatic so the VPN decides, or — without a VPN — use an encrypted public resolver such as Quad9 or Cloudflare DNS. Then rerun the test.

Question 5

Does this test work with any VPN?

Accepted Answer

Yes. The test is sponsored by RapidTunnel but reports the same facts for any setup: which resolvers answered and whether they belong to the network carrying your traffic, a public resolver, or somewhere else.