WebRTC Leak Test — Check for IP Leaks

The WebRTC Leak Test on 101IP checks whether your browser reveals your real IP address through WebRTC technology — even when using VPN, proxy or Tor.

What is WebRTC and why does a leak occur?

WebRTC (Web Real-Time Communication) is a browser technology for video calls, voice chats and peer-to-peer file transfers. When establishing a connection, the browser enumerates all available network interfaces and exposes them as ICE candidates. This can reveal the local and even public IP address — the one assigned by your ISP — bypassing the VPN tunnel.

How this test works

• the server detects your IP via HTTP headers (what any website sees);
• the browser creates a WebRTC connection and gathers ICE candidates via a STUN server;
• all IP addresses — local and public — are extracted from the candidates;
• results are compared: if WebRTC revealed a public IP different from the server's — that's a leak.

How to interpret the result

• No leak — WebRTC did not reveal additional public IPs or they match what the server sees;
• Possible leak — WebRTC revealed a public IP different from the server's: your real IP may be visible;
• Local IPs only — browser hid public addresses via mDNS (Chrome), no leak.

How to fix a WebRTC leak

• use a VPN with built-in WebRTC leak protection;
• in Firefox: set media.peerconnection.enabled = false in about:config;
• install the WebRTC Control or uBlock Origin extension with WebRTC blocking;
• in Chromium browsers, disable WebRTC via flags or extensions.

Bookmark this page and check periodically — especially after updating your browser or VPN client.