When you want to remain anonymous on the Web, the best solution is to use a VPN to hide your IP address, ISP, and location. This system prevents anyone from spying on your connection. However, a DNS leak can negate the action of the VPN. We will explain how to avoid this leak.

What is a DNS Leak?

The DNS system links the domain names and IP addresses of the target servers. When you use your browser to access a website, it sends a request to a DNS server with the desired URL, and that directs you to the correct IP address. It’s a crucial part of the Internet.

Usually, DNS servers are automatically assigned to you by your ISP (Internet Service Provider), which means that it can monitor and record your online activities each time you send a request to the server. When you use a VPN (Virtual Private Network), the DNS query is then directed to an anonymous DNS server that manages your VPN, not you’re ISP, which has no way to monitor you. In the case where your VPN does not propose dedicated private DNS, it is strongly advised to go through alternative free DNS (see a little further down in the solutions section). But then, what is the problem?

Unfortunately, sometimes your web browser ignores the presence of your VPN and sends the DNS request directly to your ISP. This is called a DNS Leak. When this happens, you think that you are browsing the Internet anonymously and avoiding online monitoring, even though you are not protected at all.

Obviously, this is problematic, and we will help you diagnose and fix a DNS Leak.

The diagnosis of DNS leak

If your computer uses the default settings and not routing DNS queries through the VPN’s DNS server, detecting the leak will not be obvious. To detect a possible leak, you then need to perform a DNS Leak test.

Once the test is done, you just have to check if the DNS of your ISP appear in place of those of your VPN. If the DNS of your VPN are not the ones detected then you undergo a leak of DNS or a “DNS LEAK “.

Stop the leak

After diagnosing the leak, it is necessary to stop it and to prevent any future DNS Leaks. We will start with the simplest solution:

Change DNS server

If your default DNS server is the one that has been assigned by your ISP, the easiest way to prevent your ISP from monitoring you is to change the DNS server. Even though monitoring your web activity is not your concern, changing the default DNS server might be a good idea, as it can give you faster internet speed.