Introduction: The Hole in the Shield
You turn on your VPN, you see a new IP address, and you feel safe. But what if your computer is still sending your DNS requests through your local ISP's servers instead of the VPN's secure ones? This is called a DNS Leak, and it is the #1 way that 'protected' users accidentally reveal their true identity and location to the world.
In this guide, we'll explain how DNS leaks happen and how you can patch them to ensure your privacy is airtight.
How a DNS Leak Happens
Operating systems like Windows sometimes try to be 'too helpful'. Even if a VPN is active, the OS might send a DNS request to your default ISP server because it responds slightly faster. Or, if the VPN connection glitches for a split second, your computer might revert to its standard settings. In both cases, your ISP sees exactly which websites you are visiting, even if the actual data is encrypted.
How to Detect a DNS Leak
You can't tell if you have a leak just by looking at your IP. You need to use a specialized DNS Leak Test. These tools check which DNS servers are actually responding to your computer's requests. If you see your ISP’s name in the results while your VPN is on, you have a leak.
How to Fix It
- Use a High-Quality VPN: Reputable VPNs have built-in 'DNS Leak Protection' that forces all queries through their tunnel.
- Set DNS Manually: Change your computer's settings to use a neutral DNS like Cloudflare (1.1.1.1) so you aren't reliant on your ISP.
- Disable IPv6: Sometimes leaks happen through IPv6 while the VPN is only protecting IPv4. Disabling IPv6 can often fix a persistent leak.
Conclusion
A leak is a silent privacy killer. Regularly testing your connection is the only way to be sure that your 'private' browsing is actually private. Run a DNS Leak test here.