DNS Leak Test

Think of DNS as your internet phone book - every time you type a website address, your device needs to "look up" the actual server location. A DNS leak happens when these lookups slip past your VPN's protection and go straight to your internet provider instead of through your VPN's secure servers.

Basically, while your VPN is encrypting your browsing traffic, your ISP can still see exactly which websites you're visiting because those DNS requests are escaping the tunnel. It's like having a bulletproof car but leaving the windows down.

Most DNS leaks happen because of how operating systems handle internet connections. Windows is particularly notorious for this - it has a "helpful" feature that sends DNS requests to multiple servers at once, including your ISP's servers, even when you're connected to a VPN.

Sometimes it's an IPv6 issue. If your internet provider supports the newer IPv6 protocol but your VPN only handles IPv4 traffic, those IPv6 requests will slip right past your VPN protection. Other times it's just poor VPN software that doesn't properly capture and route all your DNS traffic.

You might also have manual DNS settings configured on your computer that override your VPN's settings, or your system might simply be prioritizing the wrong network connection.

Your ISP can see every single website you visit, when you visit it, and how often you return. They'll know your real IP address and location, which completely defeats the point of using a VPN in the first place.

Over time, this creates a detailed profile of your browsing habits. If you're trying to access blocked content or maintain privacy, DNS leaks essentially announce your intentions to your ISP and potentially government authorities. Even seemingly innocent browsing can be problematic when combined with other data to identify you personally.

The easiest solution is choosing a VPN that automatically handles DNS protection - most quality VPN services now include this feature. If you're experiencing leaks, try manually setting your computer's DNS servers to match your VPN provider's servers.

For persistent issues, you might need to disable IPv6 entirely if your VPN doesn't support it properly. Some people prefer using independent DNS services like Cloudflare (1.1.1.1) or Quad9, though this doesn't provide the same anonymity as using your VPN's DNS servers.

After making changes, always clear your DNS cache and run a leak test to make sure the fix worked. Sometimes you'll need to restart your network connection or even reboot your computer for changes to take effect.

DNS leak tests are cleverly simple. When you visit a test page, it loads several resources from special domains that exist solely for testing purposes. As your browser tries to load these resources, it has to make DNS requests to figure out where these test domains are located.

The test monitors which DNS servers respond to these requests. If you're properly protected by a VPN, only your VPN provider's DNS servers should respond. If you see responses from your ISP's servers or other unexpected locations, you've got a leak.

More sophisticated tests run multiple queries over time to catch intermittent leaks that might not show up in a single test.

IPv4 leaks involve the traditional internet addresses most people are familiar with, while IPv6 leaks happen on the newer, longer address system that's gradually replacing IPv4.

The main problem is that many VPN providers still don't fully support IPv6, so even if your IPv4 traffic is perfectly protected, your IPv6 requests might be going directly to your ISP. This is becoming more common as internet providers roll out IPv6 support.

IPv6 leaks can actually be worse for privacy because IPv6 addresses sometimes contain information about your device's hardware, making you easier to track across different networks.

WebRTC leaks are a different animal entirely, but they're equally dangerous for VPN users. WebRTC is a browser technology that helps websites establish direct connections for things like video calls, but it can also expose your real IP address by bypassing your VPN entirely.

While DNS leaks show what websites you're visiting, WebRTC leaks reveal where you actually are. They often happen together, creating a double privacy breach. The good news is that WebRTC leaks are easier to fix - you can usually disable WebRTC in your browser settings or install an extension that blocks these requests.

Without a VPN, your DNS requests normally go to your ISP anyway, so it's not really a "leak" in that context. However, you might still want to use alternative DNS servers for privacy reasons.

Many people configure third-party DNS services even without a VPN to avoid ISP monitoring, bypass content filters, or simply get faster and more reliable service. This is especially important on public WiFi networks where you can't trust the provided DNS servers.

The privacy benefits aren't as strong as using a VPN, but switching DNS providers can still reduce tracking and improve your browsing experience.

Most reputable DNS leak test sites are perfectly safe to use. They don't require personal information and typically only reveal which DNS servers you're using - information that's already somewhat public anyway.

However, you should stick to well-known testing services and avoid any site that wants you to download software or provides suspicious results. Some shady test sites might actually be collecting data about visitors or serving malware through ads.

When in doubt, use multiple test sites to verify your results, and consider using testing tools provided by established VPN companies or privacy organizations rather than random websites you find through search engines.

DNS leak protection specifically stops your domain name lookups from escaping your VPN tunnel. It's always running in the background, quietly redirecting DNS requests to keep them secure.

A kill switch is more dramatic - it's an emergency brake that cuts off all internet access if your VPN connection drops. Think of DNS leak protection as preventing a slow privacy leak, while a kill switch prevents a sudden, complete exposure if your VPN fails entirely.

You really want both features working together. DNS leak protection handles the subtle, ongoing threats, while the kill switch protects you during those moments when your VPN connection hiccups or fails completely.