DNS Leak Test

DNS Leak Test Suite

Detecting Servers

Analyzing DNS Config

Test Complete

DNS queries detection ready

Run the test to check if your VPN or proxy is properly protecting your DNS queries.

Ready to Test Your DNS Configuration

This test will detect DNS leaks in your connection and identify if your VPN or proxy is properly protecting your DNS queries.

DNS Leaks Compromise Privacy

When using a VPN, your DNS requests should go through the VPN's servers. If they leak to your default ISP DNS servers, websites you visit can be tracked.

What is a DNS leak?

A DNS leak occurs when your DNS requests are processed by your ISP's DNS servers instead of your VPN's DNS servers, potentially exposing your browsing activity.

DNS Leak Diagram

DNS Request Exposure

When you connect to a VPN, all your internet traffic should be routed through an encrypted tunnel. However, if your device is still using your ISP's DNS servers instead of the VPN's DNS servers, your browsing activity can be exposed to your ISP and potentially to other third parties.

Privacy Implications

DNS leaks can reveal which websites you visit, even when using a VPN. This undermines the privacy protection you expect from your VPN service.

Security Risks

Beyond privacy concerns, DNS leaks can expose you to security risks like DNS poisoning attacks, where attackers redirect your traffic to malicious websites.

How to fix DNS leaks

Protect your privacy by preventing DNS leaks with these effective solutions.

Use VPN Master Pro

Our VPN service includes built-in DNS leak protection that ensures all your DNS requests are securely routed through our encrypted servers.

Enable DNS Protection

Ensure that your VPN's DNS leak protection feature is enabled in the settings. VPN Master Pro enables this by default for maximum security.

Disable WebRTC

WebRTC can leak your real IP address even when using a VPN. Disable it in your browser or use our browser extension that handles this automatically.

How does it work?

VPN Master Pro secures your DNS requests through a simple but powerful process.

1

To go to the site you want, you enter its name in the browser bar, or follow the link.

2

VPN Master Pro client turns the site name into an encrypted code and sends it over a secure channel to its own DNS server.

3

DNS-server VPN Master Pro instantly receives the IP-address of the requested site and transmits it back to the user in encrypted form.

4

You gain access to the site, with all request data and your real location hidden from your ISP and third parties.

Download VPN Master Pro
VPN DNS Protection Diagram

Complete Guide to DNS Leaks and Privacy Protection

DNS leaks are one of the most common and dangerous privacy vulnerabilities that can expose your browsing activity even when using a VPN. Understanding what DNS leaks are, how they happen, and how to prevent them is crucial for maintaining true online privacy. This comprehensive guide explains everything you need to know about DNS leak protection.

Understanding DNS: The Internet's Phone Book

Before diving into DNS leaks, it's important to understand what DNS (Domain Name System) does and why it matters for your privacy.

What is DNS?

DNS is the system that translates human-readable domain names (like vpnmasterpro.com) into IP addresses (like 192.0.2.1) that computers use to communicate. Every time you visit a website, your device performs a DNS query to look up the site's IP address.

Think of DNS as the internet's phone book. Just as you look up a person's name to find their phone number, your computer looks up a website's domain name to find its IP address. This process happens automatically and invisibly every time you:

  • Type a URL into your browser
  • Click on a link
  • Load images, videos, or scripts from external sources
  • Send or receive emails
  • Use any internet-connected application

The DNS Resolution Process

Here's what happens when you visit a website:

  1. You request a website: You type "example.com" in your browser
  2. DNS query sent: Your device asks a DNS server "What's the IP address for example.com?"
  3. DNS lookup: The DNS server searches its database for the corresponding IP address
  4. Response received: The DNS server responds with the IP address (e.g., 93.184.216.34)
  5. Connection established: Your browser connects to that IP address and loads the website

By default, your Internet Service Provider (ISP) handles these DNS queries. This means your ISP can see every website you visit, creating a complete log of your browsing history.

What Exactly is a DNS Leak?

A DNS leak occurs when your DNS queries bypass your VPN's encrypted tunnel and are sent to your ISP's DNS servers instead of your VPN provider's secure DNS servers. This defeats one of the main purposes of using a VPN—keeping your browsing activity private.

Why DNS Leaks Are Dangerous

When a DNS leak occurs, even though your IP address is hidden by the VPN, your ISP can still see:

  • Every website you visit: Complete domain names of all sites you access
  • When you visit them: Precise timestamps of your browsing activity
  • How often: Frequency of visits to specific sites
  • Duration patterns: How long you typically spend on certain types of sites

This information can be used to:

  • Build detailed profiles of your interests and behavior
  • Serve targeted advertising based on your browsing history
  • Sell your data to third parties and data brokers
  • Comply with government requests for browsing records
  • Throttle bandwidth for specific types of content

Common Causes of DNS Leaks

1. Operating System DNS Settings

Windows, macOS, and Linux all handle DNS differently. Some operating systems are configured to use multiple DNS servers and may send queries to your ISP's DNS even when a VPN is active. This is particularly common with:

  • Windows 10/11: Smart Multi-Homed Name Resolution can cause leaks
  • Windows 8/8.1: Teredo IPv6 transition technology can bypass VPNs
  • macOS: Multiple network adapters may use different DNS servers

2. IPv6 Leaks

Many VPNs only route IPv4 traffic through their servers, leaving IPv6 connections exposed. Since IPv6 has its own DNS infrastructure, queries can leak through unprotected IPv6 connections even when your IPv4 traffic is secured.

Modern websites increasingly support IPv6, and your ISP might provide IPv6 connectivity. If your VPN doesn't properly handle IPv6, your DNS queries could leak through this channel.

3. VPN Software Configuration Issues

Improperly configured VPN software can fail to properly route DNS traffic through the encrypted tunnel. Common configuration problems include:

  • Missing or incorrect DNS server settings in the VPN configuration
  • Firewall rules that don't block non-VPN DNS traffic
  • Split tunneling misconfiguration allowing DNS leaks
  • VPN reconnection delays that allow brief DNS leaks

4. Transparent DNS Proxying

Some ISPs and networks use transparent DNS proxies that intercept all DNS traffic on port 53, regardless of the intended destination. This means even if your VPN is configured correctly, your ISP might still intercept and log your DNS queries.

5. Manual DNS Configuration

If you've manually configured DNS servers (like Google's 8.8.8.8 or Cloudflare's 1.1.1.1) in your operating system settings, these might override your VPN's DNS settings, causing leaks. While these third-party DNS servers are better than your ISP's for privacy, they still create a record of your browsing outside the VPN tunnel.

How to Detect DNS Leaks

Using Our DNS Leak Test Tool

Our free DNS leak test tool makes it easy to check if your VPN is properly protecting your DNS queries:

  1. Connect to your VPN: Ensure your VPN is active and connected
  2. Run the test: Our tool automatically queries multiple DNS servers
  3. Review results: Check if the DNS servers belong to your VPN provider or your ISP
  4. Verify location: Ensure all DNS servers show your VPN's location, not your real location

What the Results Mean

No DNS leak detected: All DNS servers should belong to your VPN provider and show the VPN server's location. This indicates your DNS queries are properly protected.

DNS leak detected: If you see DNS servers belonging to your ISP or showing your real location, you have a DNS leak. This means your browsing activity is being exposed despite using a VPN.

Mixed results: Seeing both VPN and ISP DNS servers indicates a partial leak—some queries are protected while others aren't. This is still a serious privacy vulnerability.

How to Fix DNS Leaks

1. Use a VPN with Built-in DNS Leak Protection

The most reliable solution is to use a VPN service that includes robust DNS leak protection. Premium VPNs like VPN Master Pro provide:

  • Private DNS servers: Exclusive DNS infrastructure operated by the VPN provider
  • Automatic DNS configuration: VPN software automatically configures your device to use only VPN DNS
  • IPv6 protection: Either routes IPv6 through the VPN or blocks it to prevent leaks
  • DNS leak prevention: Firewall rules that block all non-VPN DNS traffic

2. Disable IPv6

If your VPN doesn't support IPv6, disabling it prevents IPv6 DNS leaks:

Windows: Network Connections → Adapter Properties → Uncheck "Internet Protocol Version 6 (TCP/IPv6)"

macOS: System Preferences → Network → Advanced → TCP/IP → Configure IPv6: Off

Linux: Edit /etc/sysctl.conf and add: net.ipv6.conf.all.disable_ipv6 = 1

3. Configure Manual DNS Settings

Some VPNs require manual DNS configuration. Use your VPN provider's DNS servers:

  • Access your network adapter settings
  • Set DNS servers to your VPN provider's DNS addresses
  • Remove any ISP or third-party DNS servers
  • Ensure "Obtain DNS server address automatically" is unchecked

4. Use a VPN Kill Switch

A kill switch blocks all internet traffic if the VPN connection drops, preventing DNS leaks during reconnection:

  • Monitors VPN connection status continuously
  • Instantly blocks traffic if VPN disconnects
  • Prevents accidental exposure during connection interruptions
  • Automatically resumes traffic when VPN reconnects

5. Flush DNS Cache

After changing DNS settings, flush your DNS cache to ensure old entries are cleared:

Windows: ipconfig /flushdns in Command Prompt

macOS: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Linux: sudo systemd-resolve --flush-caches or sudo /etc/init.d/nscd restart

Advanced DNS Leak Prevention

DNS over HTTPS (DoH)

DNS over HTTPS encrypts DNS queries within HTTPS traffic, making them harder to intercept or block:

  • Encrypts DNS queries end-to-end
  • Prevents ISP inspection of DNS traffic
  • Bypasses transparent DNS proxies
  • Supported by modern browsers like Firefox and Chrome

Major DoH providers include Cloudflare (1.1.1.1), Google (8.8.8.8), and Quad9 (9.9.9.9). However, using these with a VPN may create privacy concerns as they operate outside your VPN tunnel.

DNS over TLS (DoT)

Similar to DoH but uses a dedicated port (853) for encrypted DNS:

  • Provides encrypted DNS queries
  • Easier for networks to identify and manage
  • Supported by Android 9+ and some VPN software
  • May be blocked by restrictive networks

DNSCrypt

A protocol that encrypts and authenticates DNS traffic:

  • Prevents DNS spoofing and manipulation
  • Encrypts queries between your device and DNS server
  • Requires specific software to implement
  • Supported by some privacy-focused VPNs

Testing for Other Privacy Leaks

DNS leaks are just one type of privacy vulnerability. For comprehensive protection, also check for:

Best Practices for DNS Privacy

Choose a No-Logs VPN

Even with perfect DNS leak protection, your VPN provider can see your DNS queries. Choose a provider with a verified no-logs policy:

  • Third-party audited no-logs claims
  • Privacy-friendly jurisdiction (outside 5/9/14 Eyes)
  • Transparent privacy policy
  • No DNS query logging
  • RAM-only servers that can't store logs

Regular Testing

Test for DNS leaks regularly, especially:

  • After installing or updating VPN software
  • When changing VPN servers
  • After operating system updates
  • When connecting from new networks
  • If you suspect privacy issues

Layer Your Privacy Protection

Combine multiple privacy tools for defense in depth:

  • Use a VPN with DNS leak protection
  • Enable DNS over HTTPS in your browser
  • Use privacy-focused browsers like Firefox or Brave
  • Install tracker-blocking extensions
  • Clear cookies and cache regularly

Frequently Asked Questions

What is a DNS leak and why does it matter?

A DNS leak occurs when your DNS queries bypass your VPN and are sent to your ISP's DNS servers, exposing your browsing activity. This defeats the privacy protection of your VPN, allowing your ISP to see every website you visit even though your IP address is hidden. DNS leaks can happen due to OS configuration, IPv6 connections, or improper VPN settings.

How do I know if my VPN is leaking DNS queries?

Use our free DNS leak test tool while connected to your VPN. If the test shows DNS servers belonging to your ISP or your real location instead of your VPN provider, you have a DNS leak. A properly configured VPN should only show DNS servers operated by your VPN provider in the VPN server's location.

Can my ISP see my browsing with a DNS leak?

Yes, with a DNS leak your ISP can see the domain names of every website you visit and when you visit them, even though your actual traffic is encrypted by the VPN. They see the DNS queries that reveal which sites you're accessing, allowing them to build a complete profile of your browsing activity. This is why DNS leak protection is critical for true privacy.

How do I fix a DNS leak?

The best solution is to use a VPN with built-in DNS leak protection like VPN Master Pro. You can also manually configure your device to use only your VPN's DNS servers, disable IPv6 if not supported by your VPN, enable your VPN's kill switch, and configure firewall rules to block non-VPN DNS traffic. After making changes, always test again to verify the leak is fixed.

What's the difference between DNS leak and IP leak?

An IP leak exposes your actual IP address and physical location, while a DNS leak exposes your browsing history through DNS queries. You can have a DNS leak even when your IP is properly hidden—your VPN successfully masks your IP but DNS queries still go to your ISP. Both types of leaks compromise privacy and should be prevented for complete protection.

Should I use Google DNS or Cloudflare DNS with a VPN?

When using a VPN, you should use your VPN provider's DNS servers, not third-party DNS like Google (8.8.8.8) or Cloudflare (1.1.1.1). While these third-party DNS services are privacy-focused, using them with a VPN creates queries outside the VPN tunnel that can be logged. Your VPN's DNS servers keep all queries within the encrypted tunnel for maximum privacy.

Conclusion

DNS leaks are a serious privacy vulnerability that can expose your entire browsing history even when using a VPN. Understanding how DNS works, what causes leaks, and how to prevent them is essential for maintaining true online privacy.

The good news is that DNS leaks are preventable with the right tools and configuration. By using a VPN with built-in DNS leak protection, properly configuring your device, and regularly testing for leaks, you can ensure your browsing activity remains private.

Remember that privacy is not a one-time setup—it requires ongoing vigilance. Test regularly using our free DNS leak test tool, especially after software updates or network changes. Combined with other privacy measures like using privacy-focused browsers and blocking trackers, DNS leak protection helps you maintain control over your personal data.

Don't let DNS leaks undermine your VPN's protection. Test your connection now and take action if leaks are detected. Your online privacy is worth protecting.

Protect Your DNS Privacy Today

Use our free DNS leak test to check if your VPN is properly protecting your browsing activity. Then secure your connection with a trusted VPN service.

Frequently Asked Questions About DNS Leaks