The CryptoIP DNS leak test can help prevent DNS leaks by showing you which DNS servers your device uses for name resolution.
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How to Test for DNS Leaks

DNS leak testing is simple. Just click on the Advanced Test button to do in-depth testing which is six rounds of five DNS queries or standard testing which is one round of five DNS queries.

What Is A DNS Leak

The Domain Name System (DNS) is used to translate domain names like to an IP address like This translation is needed to route packets of data around the Internet. When you connect to a website, your device asks a DNS server for the IP address. Most ISPs assign customers a DNS server under its control and use it to log the websites you visit and how often you visit them.

When you use a virtual private network (VPN), all of the network traffic coming from your device gets routed through the VPN servers, including DNS requests. Sometimes, though, your web traffic is accidentally leaked outside of this secure connection. Anyone who monitors your network traffic can pick up these DNS leaks and log your activity.

What Causes A DNS Leak

Under certain conditions, even when using a VPN or proxy, your operating system will revert to using its default DNS server assigned by the ISP, instead of anonymous DNS servers provided by the VPN provider.

In Windows, each adapter has a set of DNS servers defined. When a DNS query is made, Windows uses the fastest responding DNS server which will be your router's built-in DNS forwarder. The router forwards the request off to your ISP or Google DNS, and the queries are stored there forever.

There is another type of DNS leak that requires an attacker to force your device to route DNS traffic through the Internet instead of through the VPN. This kind of attack requires DNS servers that are publically available.

Why DNS Leaks Need to be Prevented

DNS leaks are important because your online privacy is at stake. ISPs and "free DNS providers" like Google are monitoring your browsing habits. Worse yet, some ISPs take it a step further and inject advertisements onto the page your browsing. If you care about your privacy, you should care about DNS leaks. DNS leaks are especially worrisome because many VPN users do not even realize DNS leaks are happening.

How LiquidVPN Can Help

LiquidVPN is one of a small group of VPNs that come with built-in protection against DNS leaks. Moreover, DNS leak protection happens automatically. All you have to do is open the LiquidVPN client, go into Settings, and make sure that the DNS setting is set to automatic. If your device is vulnerable to other harder to stop leaks, you can enable Liquid Lock. Liquid Lock is a feature of LiquidVPN that forces all of your device’s traffic including DNS requests to pass through LiquidVPN servers. Liquid Lock blocks DNS leaks, data leaks and even IP leaks like WebRTC.

WebRTC was first documented by Daniel Roesler, a developer in San Francisco. The flaw lets websites find out your actual IP address using WebRTC, which is built into most web browsers.

This vulnerability is possible because WebRTC allows requests sent to your ISP's STUN servers to return your public and local IP addresses using JavaScript. Since the STUN requests are not made using XMLHttpRequest, they cannot be blocked with privacy plugins like Ghostery or AdBlockPlus.