{"description":"What DNS leaks, WebRTC leaks, and IPv6 leaks are, why they can reveal you while the VPN is on, and what you can check and change yourself.","language":"en","latest_measurement":"2026-10-17","method":"latency-v3","method_page":"https://crackthe.net/method/","source":"https://crackthe.net/","text":"Key points\nA leak means some of your traffic or your real address reaches the outside world past the VPN tunnel. DNS leak: your device asks your internet provider, not the VPN, which address belongs to a website name. Your provider then sees which sites you visit. WebRTC and IPv6 leaks can reveal your real address to a website. Good VPN apps block all three; check the settings. How a DNS leak happens Before your browser opens a website, it asks a DNS server for the site\u0026rsquo;s address. With the VPN on, this question should go through the tunnel to the VPN\u0026rsquo;s DNS server. If it goes to your internet provider instead, the provider learns the names of the sites you open, even though the pages themselves travel through the VPN.\nYour deviceasks where a site is Your internet provideranswers, and learns the site name VPN servercarries the page itself encrypted by the VPN not encrypted by the VPN\nA DNS leak: the page goes through the tunnel, but the question about the site\u0026#39;s address does not. Three kinds of leaks LeakWhat slips outWho sees itWhat helps DNS leakthe names of the sites you openyour internet providerthe VPN app\u0026rsquo;s own DNS setting WebRTC leakyour real IP addressthe website, through the browserthe app\u0026rsquo;s WebRTC protection or browser settings IPv6 leakyour real IPv6 addressthe websitean app that routes or blocks IPv6 What you can check on this site The IP check shows the address that reaches this website and its type, IPv4 or IPv6. If it shows an IPv6 address that is not your VPN\u0026rsquo;s while the VPN is on, your IPv6 traffic bypasses the tunnel.\nThe IP check does not test for DNS or WebRTC leaks. For those, you need a test that runs its own DNS server or reads your browser\u0026rsquo;s WebRTC data. Many VPN providers offer such a test on their website.\nSettings that prevent leaks Use the app\u0026rsquo;s own DNS. Most VPN apps have a setting like \u0026ldquo;use VPN DNS\u0026rdquo; or \u0026ldquo;DNS leak protection\u0026rdquo;. Keep it on. Turn on the kill switch, so nothing leaves your device when the tunnel drops. Check IPv6. If your app does not support IPv6, turn on its option to block IPv6, or turn IPv6 off on the device. Use the VPN app, not only a browser extension. Many extensions only cover the browser and only act as a proxy. Apps are not tested on this site. Whether a particular app blocks leaks cannot be checked from outside. Use the refund period to test it yourself.\nNext step Read Geoblocking, explained to see how websites decide which country you are in.","title":"DNS and WebRTC leaks: when your real address slips out","url":"https://crackthe.net/learn/dns-and-webrtc-leaks/"}