How to Perform a DNS Leak Test?

Domain Name System is a foundation of the internet that people may not even have heard of. It is basically a directory of names and numbers, with names being the domain names and numbers being the IP addresses. The job of the DNS is to resolve domain names into IP addresses. In simple words, whenever you type a domain then in your web browser then a request is sent to the DNS server which then provides your browser with the correct IP address of that domain to connect to the websites.

The basic job of the DNS is to match correct names with correct numbers or correct domain names with correct IP addresses.

What is a DNS leak?

As mentioned earlier that your browser takes the help of DNS servers to process your requests. When you connect to a VPN or Virtual-Private Network then all of your online traffic is routed through a secure, encrypted VPN network and this also includes the DNS queries. However, when there is a DNS leak then the DNS queries instead of going through the encrypted tunnel go through the default DNS servers which belong to your ISP and hence expose your online traffic.

A DNS Leak is a security flaw and exposes your online activity to your ISP which wouldn’t happen without a DNS leak.

A DNS Leak occurs due to the following reasons:

  • You reset the system settings
  • You are using the Smart Multi-Homed Name Resolution feature on Windows 8 or later
  • You set up a VPN manually
  • You are using a VPN service that doesn’t have its own DNS servers and doesn’t provide protection against DNS leaks

The effect of DNS leak is that once your online traffic starts going through the ordinary DNS of your ISP then it will be visible to the ISP and there will be no point in using the VPN to gain anonymity. And you won’t know about all this unless you perform a DNS leak test, which tests out your VPN provider and your connection, whether there is a DNS leak or not.

How to Perform a DNS Leak Test?

When you perform a DNS Leak Test then you will be able to check if there a DNS leak or not. Performing a DNS Leak Test is easy and here is how you can perform a DNS Leak Test yourself:

  1. Visit the DNS Leak Test Website.
  2. There it will show the basic information regarding your internet connection such as your location and IP address.
    (If you are connected to a VPN then the IP address and location won’t match your real ones, however, if you are not then your real location and IP address will be shown.)
  3. To perform a DNS Leak Test, select either Standard Test or Extended Test. If you are connected to a VPN server and the test will show the DNS servers that are being used to process your queries.

If the test shows DNS servers that don’t belong to your ISP then it means that there is no DNS leak, however, if the servers belong to your ISP then there is a DNS leak in your VPN Connection.