WebRTC Leak Test

What this tool does

WebRTC Leak Test gathers ICE candidates via a local RTCPeerConnection, using a single public STUN server for discovery, to reveal which local and public IP addresses WebRTC would expose to any website, a known technique some VPNs and proxies fail to intercept, potentially leaking your real IP even while connected.

WebRTC, the technology behind browser-based video calling, needs to discover a device’s network addresses to establish a peer-to-peer connection, and it does this through a separate network path (ICE candidate gathering) that some VPNs and proxies, especially older or poorly configured ones, fail to route through their tunnel, potentially exposing your real IP even while "protected".

This test runs that same ICE candidate gathering process (using one public STUN server purely for address discovery) and shows you exactly which local and public IP addresses it reveals, letting you check whether a VPN you’re relying on actually blocks this specific leak vector.

How to use WebRTC Leak Test

1. Press Scan for WebRTC IP leaks.
2. Wait a few seconds for candidate gathering to complete.
3. Review the discovered addresses and their classification (private/public/link-local).
4. Compare any public address against your VPN’s stated exit IP if you’re checking for a leak.

Tips for better results

• If you’re using a VPN, compare any "Public" classified address here against your VPN’s actual exit IP (check What Is My IP separately); if they differ and show your real ISP-assigned address instead, that’s a genuine leak.
• Seeing no addresses, or only a locally-administered "host" candidate with no real local network info, is expected and good on modern browsers, which increasingly use random mDNS hostnames to obscure local network addresses by default.
• Some VPN providers explicitly address this by either blocking WebRTC’s UDP traffic at the OS/network level, or by routing it correctly through their tunnel, check your VPN’s documentation if a leak is found.
• This test uses only a single public STUN server purely for address discovery, no actual video/audio call or peer connection is ever established.

Common use cases

• Checking whether a VPN you’re using actually prevents a known IP leak vector.
• Verifying a privacy-focused browser configuration or extension correctly blocks WebRTC leaks.
• Understanding, with a live example, how ICE candidate gathering can reveal network information.
• Auditing your own network privacy setup before relying on it for something sensitive.

Common mistakes to avoid

• Assuming a VPN automatically prevents this leak just because it’s connected, not every VPN client intercepts WebRTC’s UDP-based ICE traffic by default, this test exists specifically to verify that assumption.
• Panicking over a "host" (local network) candidate showing a private address like 192.168.x.x, that’s your normal local network address and isn’t a privacy concern on its own; the real check is whether a "srflx" (public) candidate matches your VPN exit IP or your real ISP IP.
• Confusing this with a full network security audit; it specifically tests one known leak vector (WebRTC ICE gathering), not your overall VPN or browser security posture.