DNS · WebRTC · IP Leaks · How to Fix
Connect your VPN, then visit these test sites to check for leaks:
| Test | What to Check | Site |
|---|---|---|
| IP Leak | Should show VPN server IP, not your real IP | ipleak.net |
| DNS Leak | DNS servers should match VPN provider, not ISP | dnsleaktest.com |
| WebRTC Leak | Should not show local IP address | browserleaks.com/webrtc |
| IPv6 Leak | Should show no IPv6 or VPN's IPv6 | test-ipv6.com |
Run ALL four tests while connected to VPN. If any show your real IP or ISP, you have a leak.
| Leak Type | What Leaks | Risk Level | Common Cause |
|---|---|---|---|
| DNS Leak | Which websites you visit | High | OS uses ISP DNS instead of VPN DNS |
| WebRTC Leak | Your real IP address | Critical | Browser WebRTC reveals local IP |
| IPv6 Leak | Your IPv6 address | Medium | VPN only tunnels IPv4 traffic |
| Kill Switch Failure | All traffic during reconnect | Critical | VPN drops, traffic flows unprotected |
| Leak | Fix |
|---|---|
| DNS Leak | Enable "Use VPN DNS" in settings. Manually set DNS to 1.1.1.1 or VPN provider's DNS. |
| WebRTC Leak | Disable WebRTC in browser: Firefox (about:config → media.peerconnection.enabled = false) or use extension. |
| IPv6 Leak | Enable "Block IPv6" in VPN settings. Or disable IPv6 in OS network settings. |
| Kill Switch | Always enable kill switch in VPN app settings. Test by disconnecting VPN — internet should stop. |
| Provider | DNS Protection | WebRTC Block | Kill Switch | IPv6 Block |
|---|---|---|---|---|
| NordVPN | ✓ | ✓ | ✓ | ✓ |
| ExpressVPN | ✓ | ✓ | ✓ | ✓ |
| Surfshark | ✓ | ✓ | ✓ | ✓ |
| Mullvad | ✓ | ✓ | ✓ | ✓ |
| Free VPNs | ✗ | ✗ | ✗ | ✗ |
🔒 VPN leak testing should be performed after every major VPN app update and on new devices. Even premium VPNs can occasionally leak during reconnection — a kill switch is your last line of defense.