WebRTC (Web Real-Time Communication) is a browser feature that lets websites provide video calls, voice chat, and peer-to-peer file sharing without plugins. To work properly, it needs to discover your device's IP addresses, including your real one behind any VPN tunnel.
A WebRTC leak occurs when websites can see your genuine IP address through this discovery process, bypassing your VPN's encryption. This happens because WebRTC queries your system for all available network interfaces and exposes them to JavaScript running on web pages. Even if your VPN successfully masks your IP for normal traffic, WebRTC requests can slip around it.
Why this matters
If you rely on a VPN for privacy or to appear in a different location, a WebRTC leak undermines that protection. Advertisers, data brokers, and malicious sites can identify your true location and link your activity across sessions, defeating the purpose of using a VPN.
How to check and prevent leaks
- Use online WebRTC leak test tools to see if your real IP is exposed
- Disable WebRTC in your browser settings or via extensions
- Choose a VPN with built-in WebRTC leak protection
- Use browsers with stricter privacy defaults (Firefox, Brave)
- Keep your browser and VPN software updated, as developers patch this vulnerability regularly
Not all users need to worry about WebRTC leaks, but anyone relying on a VPN for serious privacy work should test their setup.