Performing a regular DNS Leak Test is essential for anyone who values their online anonymity and wants to verify that their virtual private network is truly shielding their browsing habits. Even when your web traffic travels through an encrypted tunnel, misconfigured network settings can cause your device to send domain name resolution requests directly to your Internet Service Provider (ISP), exposing every website you visit.

DNS Leak & Encrypted DNS (DoH) Tester

Determine if your browser or VPN is leaking unencrypted DNS queries to your Internet Service Provider (ISP), exposing your visited websites and digital activity.

Why You Must Perform a DNS Leak Test

Whenever you enter a website URL into your browser, your operating system queries a Domain Name System (DNS) server to translate the human-readable domain (such as example.com) into a machine-readable IP address. By default, these queries are handled by your ISP’s DNS resolvers and transmitted in unencrypted plaintext over standard UDP/TCP port 53.

When you run our DNS Leak Test, our diagnostics analyze your resolver endpoints to verify if your queries are routed through your secure VPN tunnel or leaking back to your ISP. If your ISP resolvers appear in the test results, third parties can build a comprehensive history of your online activity, download habits, and visited domains.

Understanding Encrypted DNS: DNS-over-HTTPS (DoH) and DNS-over-TLS (DoT)

To eliminate plaintext query surveillance, modern network standards incorporate encrypted DNS protocols:

  • DNS-over-HTTPS (DoH): Encapsulates DNS queries inside standard HTTPS traffic on port 443. This prevents network eavesdroppers and public Wi-Fi operators from distinguishing DNS lookups from regular web browsing.
  • DNS-over-TLS (DoT): Uses dedicated TLS encryption over port 853 to secure communication between your resolver and root nameservers.
  • DNSSEC (DNS Security Extensions): Cryptographically signs DNS records to prevent cache poisoning and man-in-the-middle spoofing attacks.

How to Fix DNS Leaks and Secure Your Connection

  1. Enable DNS Leak Protection: In your VPN application settings, ensure ‘IPv6 Leak Protection’ and ‘Strict DNS Routing’ are activated. Cross-check your connection speed with our VPN Speed Test & Connection Inspector.
  2. Verify WebRTC Security: Test for hidden browser endpoint leaks with our WebRTC Leak & Browser Fingerprint Tester.
  3. Audit IP Routing: Inspect your public gateway details with our IP & Domain Intelligence Inspector.
  4. Consult Official Standards: Review official documentation from the IETF RFC 8484 DNS-over-HTTPS (DoH) Specification and the InterNIC Root Zone Registry.