WebRTC Leak Test
About the WebRTC Leak Test
WebRTC lets browsers make video calls and peer-to-peer connections. To do that, it asks STUN servers for your public address — and on some setups this bypasses your VPN or proxy, letting any website discover your real IP address with a few lines of JavaScript. This test performs that same check in your browser and compares the addresses WebRTC exposes with the IP websites normally see. If they differ, your VPN is leaking.
This test contacts public STUN servers to see which addresses your browser exposes, so it needs an internet connection.
How to use it
- Connect to your VPN or proxy, then open this page — the test runs automatically.
- Compare “IP websites see” with “IPs revealed by WebRTC”.
- If a leak is found, follow the fixes listed and click Run again to confirm.
Frequently asked questions
What is a WebRTC leak?
A WebRTC leak happens when your browser reveals your real public IP address (or a local network address) through WebRTC while a VPN or proxy is hiding it everywhere else. Websites can read these addresses without any permission prompt.
What does “Hidden by mDNS” mean?
Modern browsers replace your local IP with a random .local name in WebRTC, so sites can’t see your internal network address. That is the safe, expected behaviour.
Do I need to disable WebRTC completely?
Not usually. Most good VPNs block WebRTC leaks, and browser extensions can limit WebRTC to the VPN interface. Disabling WebRTC entirely also breaks browser-based video calls such as Google Meet.
Is it a leak if I’m not using a VPN?
No. Without a VPN, the public IP WebRTC shows is the same one every website already sees, so nothing extra is revealed.