Run this IPv6 leak test to determine if your VPN properly tunnels IPv6 traffic or if your real IPv6 address is bypassing the encrypted connection. Results display in under 5 seconds.

FreeGuard Internal Test Results

FreeGuard VPN tunnels both IPv4 and IPv6 traffic through the encrypted connection, with zero IPv6 leaks detected across dual-stack networks in our testing.

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Why IPv6 Leaks Are the Most Overlooked VPN Vulnerability

Many VPN providers only tunnel IPv4 traffic, leaving IPv6 requests to travel directly through your ISP and expose your real identity on the growing number of IPv6-enabled networks.

IPv6 adoption has reached approximately 45% globally, with countries like India (70%), Germany (65%), and the United States (50%) leading deployment. As more ISPs enable dual-stack networking (supporting both IPv4 and IPv6 simultaneously), the risk of IPv6 leaks grows.

An IPv6 leak occurs when your VPN only creates a tunnel for IPv4 traffic. When your device makes an IPv6 connection — which happens automatically on dual-stack networks — the traffic goes directly through your ISP, completely bypassing your VPN encryption.

This is particularly dangerous because IPv6 addresses are often unique to your device (unlike IPv4 where you might share an IP via NAT). A leaked IPv6 address can directly identify your specific device and connection.

Many users are unaware they even have IPv6 connectivity. If your ISP has enabled it, your device may be using it alongside IPv4 without any visible indication.

How VPN Providers Handle IPv6: Three Approaches Compared

VPNs handle IPv6 by either blocking it entirely, tunneling it through the VPN, or ignoring it — only the first two approaches prevent leaks.

Block IPv6 (Common): Many VPN providers disable IPv6 on your device while the VPN is active. This prevents leaks but means you cannot access IPv6-only resources. This is a safe but increasingly limiting approach as more services adopt IPv6.

Tunnel IPv6 (Best): Advanced VPN providers route both IPv4 and IPv6 traffic through the encrypted tunnel, providing full protection while maintaining IPv6 connectivity. FreeGuard VPN uses this approach.

Ignore IPv6 (Dangerous): Some VPN providers, particularly free ones, do nothing about IPv6 traffic. If your ISP provides IPv6, it leaks freely. This is the scenario our test detects.

To determine which approach your VPN uses, run this test on a network with IPv6 enabled. If you see an IPv6 address belonging to your ISP (not your VPN), you have a leak.

How to Protect Yourself in 3 Steps

1. Step 1: Connect to your VPN and run the IPv6 leak test above to check for exposed IPv6 addresses
2. Step 2: If an IPv6 leak is detected, check your VPN settings for an IPv6 leak protection option and enable it
3. Step 3: If your VPN does not support IPv6 protection, consider switching to FreeGuard VPN which tunnels both IPv4 and IPv6

Frequently Asked Questions

What is an IPv6 leak and how is it different from a regular DNS leak or WebRTC leak in terms of risk and what should I be aware of?

An IPv6 leak exposes your real IPv6 address because your VPN only tunnels IPv4 traffic. Unlike DNS leaks (which expose domains you visit) or WebRTC leaks (browser-level), IPv6 leaks reveal your unique device address.

How do I know if my internet connection uses IPv6 and whether I am at risk of an IPv6 leak and what should I be aware of?

Run this test without a VPN. If an IPv6 address appears, your connection supports IPv6 and you are at risk if your VPN does not handle it. Many ISPs enable IPv6 without notifying customers.

Can I simply disable IPv6 on my computer or router to prevent IPv6 leaks instead of using a VPN and what are the most important things I should know about this?

Yes, disabling IPv6 at the OS or router level prevents leaks, but you lose access to IPv6-only resources. A better approach is using a VPN that properly tunnels IPv6 traffic.

Why do many VPN providers still not support IPv6 tunneling even though IPv6 adoption is growing rapidly and what are the most important things I should know about this?

IPv6 tunneling requires additional infrastructure and protocol support. Many providers chose to block IPv6 as a simpler solution, but this becomes increasingly limiting as IPv6 adoption rises.

Does the hysteria2 VPN protocol handle IPv6 traffic better than trojan or trojan protocols and what are the key considerations and potential limitations that I should be aware of before proceeding?

hysteria2 natively supports dual-stack (IPv4 + IPv6) tunneling with minimal configuration. anytls and trojan also support IPv6 but require additional configuration that some providers skip.

If my VPN blocks IPv6 instead of tunneling it, what websites or services might I lose access to and what can I do to maintain full access to the content?

Most websites remain accessible via IPv4, but some newer services and IoT platforms are IPv6-preferred. You may also experience slightly slower connections if IPv6 is faster on your network.

How can I check if my mobile carrier provides IPv6 connectivity and whether my mobile VPN handles it and what are the most important things I should know about this?

Run this test on your phone using cellular data (not Wi-Fi) with and without your VPN. Most major mobile carriers now provide IPv6, making this test important for mobile VPN users.

Is it true that IPv6 addresses are more identifying than IPv4 addresses because they are unique to each device and what are the most important things I should know about this?

Yes. IPv4 addresses are often shared via NAT (many users behind one IP), while IPv6 addresses can be unique to your device. A leaked IPv6 address can directly identify your specific connection.