DNS and WebRTC tests examine different parts of your network behavior. They can reveal mismatches or unexpected addresses, but they do not by themselves prove whether a VPN, proxy or privacy setup is completely secure.
What a DNS leak means
DNS translates domain names into network addresses. When you use a privacy service, you may expect DNS queries to use that service too. A leak test looks for resolver information that appears inconsistent with the network path you intended to use. Corporate networks, mobile providers and secure DNS features can make interpretation less obvious.
What WebRTC can expose
WebRTC enables real-time browser communication. Depending on browser behavior and network configuration, it may reveal local addresses or additional public network candidates. Modern browsers have reduced several historic leak patterns, so results can vary widely by browser.
Run a before-and-after comparison
If you are testing a VPN or network change, record the result before enabling it, then repeat the same test afterward in the same browser. Compare public IP, resolver information and WebRTC candidates. A consistent comparison is more useful than a single isolated screenshot.
Know the limits of browser tests
A website can only observe what the browser and network expose to it. A clean test does not guarantee anonymity, and an unexpected resolver does not always mean a security failure. Use the provider documentation and operating-system network settings when the result matters.
Worked example
Example comparison
Run the test before enabling a VPN, record the public IP and resolver details, then repeat in the same browser after connecting. Investigate unexpected differences instead of relying on a single pass/fail label.
Practical checklist
Before you finish
- Compare results before and after a network change.
- Do not confuse local private IP addresses with public identity by themselves.
- Secure DNS settings can change resolver results.
- Use multiple signals rather than one pass/fail badge.
Common mistakes
What to avoid
- Calling every unfamiliar DNS resolver a leak without checking the network setup.
- Comparing results from different browsers or networks.
- Confusing a private local IP address with a public Internet address.
- Treating one clean test as a guarantee of anonymity.