what really is a dns leak

What Really Is A DNS Leak? Here’s A 100% Ultimate Fix?

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Last Updated on December 22, 2020 by Calvin C.

How your data is handled by network servers ?

What really is a DNS leak? You can learn more about it by going back to VPN basics.

Normally, without a VPN, your URL requests are resolved by DNS servers belonging to your ISP. This means that the latter has the ability to view your browsing data.

Consequently, if the national laws allow the government to access ISP servers, all your logged data is seen.

In addition, your ISP has an option to cash in on your data especially to advertisers. These rely heavily on knowing the browsing patterns of users.  

What you need is a VPN service that uses its DNS servers to resolve ALL your URL queries.

This means your ISP should not be able to view your browsing patterns as they are shielded by the VPN.

  • The following VPNs have no DNS leaks

What really is a DNS leak?

In some cases, a VPN service that is not robust may indicate that it uses its DNS servers.

However, some of the queries may still be visible to your ISP. This happens because by default your device resolves any DNS queries via the local ISP DNS servers.

Only a VPN that has complete DNS leak protection can shield your browsing data from the ISP.

Therefore, a DNS leak signifies an imperfection of a VPN service. All the privacy is lost once some parts of your browsing history are visible to prying eyes.

This is how you know if your IP is leaking because DNS information is knitted together with your IP address.

What causes a DNS leak?

The following are the common causes of a DNS leak:

  • Using a VPN which is not robust and is vulnerable to DNS leaks. That is why it is risky to use free VPN services that promise anonymity and security. In the process, your data leaks behind the scene. To be on the safe, always keep in mind that what you get for free is paid in another way. In most cases, you realize that when it is too late.
  • Not configuring your device properly. The default settings use the local DNS server to handle any DNS requests. Therefore, you have to ensure you are using proper DHCP settings. You may change the settings of your device unknowingly and leave it vulnerable to data leaks.
  • Using a VPN without support for IPv6 addresses. IP addresses are transitioning from IPv4 to IPV6. If internet queries involve these two versions, a DNS leak may occur. This happens when a VPN is not yet up-to-date in handling both at the same time,
  • Security flaws in Windows 8 or later. A feature called Smart Multi-Homed Name Resolution improves browsing speeds by sending DNS queries to all available DNS servers.
surfshark with no dns leak

How do you check for a DNS leak?

The only way to know if your DNS is leaking is to perform a DNS leak test. This should be a habit whenever you start using a new VPN.

Fortunately, we do that for you at VPNAnchor. Only VPN services with zero DNS leaks are recommended by us.

If you go to respective sites of top VPN providers, they have an integrated DNS leak test tool. It is good to verify results before committing to a plan.

Therefore, I recommend an independent DNS leak test tool not affiliated with any VPN. One such site that I use for DNS leak test is dnsleaktest.com.

Online checkers

Follow the steps below to do it the easy way, that is sufficient for most people:

  1. Switch on the VPN you use and make sure you are connected to a VPN tunnel
  2. Go to www.dnsleaktest.com in your browser. This is not the only site which carries out in-browser DNS leak test but it gets the job done.
  3. The site automatically checks if you have a DNS leak or not. If it shows your correct IP address and region, then there is a DNS leak. This means your VPN is not doing a good job in hiding your identity, location, and securing your data.
  4. If it displays an IP address of the country you have specified, then there is no DNS leak. This applies to the best VPNs that strictly adhere to zero-data-leakage policies.

Command prompt

This is for those who want to take a step further and avoid using online checkers. Remember, to use an online checker you need to go on the internet first and access the tool.

Take note that this action is visible to your ISP if the VPN is flawed. Follow these steps to do that in Windows:

  1. Switch on your VPN
  2. Open command prompt and enter the DNS test command line as indicated below
  3. Enter this text: ping [resolver.dnscrypt.org] –n 1
  4. Press Enter
  5. If the IP address displayed in the results is yours, then there is a DNS leak. However, if it shows the IP of a country you select on your VPN, there is no DNS leak.

How to fix a DNS leak?

If you find a DNS leak, you need to use a trusted VPN that stops any DNS leak.

The VPN services we review here on VPNAnchor have no DNS leaks so the definitive solution is as simple as selecting the best VPN service.

  • Got no time? Use our top pick with all essential features:

You also stop any IP leaks by using one of these VPNs.


DNS leaks compromise your privacy but fortunately the fix is integrated in the VPNs mentioned above. Leave comments below and share the post with your friends.

Tech writer and VPN expert. DIY enthusiast and loves anything to do with space science.

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