What Is a WebRTC Leak? The Browser Flaw That Exposes Your Real IP
WebRTC is the browser technology behind in-page video calls — it powers Meet, Discord in the browser, and countless conferencing tools. It's also the source of one of the sneakiest privacy holes on the web: a few lines of JavaScript can ask WebRTC for your IP addresses, and in bad configurations it will answer with your real IP even while a VPN is connected.
Why WebRTC exposes IPs at all
Real-time calls work best peer-to-peer. To connect two people directly through routers and NAT, WebRTC uses a discovery process (ICE/STUN) that enumerates every address a device can be reached at — local addresses, the public IP, and relay candidates. That enumeration is available to the webpage. A page doesn't need to make a call, show a permission prompt, or do anything visible — it can just ask.
When it becomes a leak
With no VPN, WebRTC revealing your public IP is redundant — every site sees it anyway. The problem is with a VPN: your normal traffic exits via the VPN, but STUN discovery may go around the tunnel and return your real public IP alongside the VPN one. A site comparing the two learns both that you use a VPN and who you really are.
How to test yourself
- Connect your VPN and confirm your apparent IP changed on our checker.
- Open a WebRTC leak test (search "WebRTC leak test").
- If the results show your real ISP address anywhere, you're leaking.
How to fix it
- Use a VPN whose app blocks WebRTC leaks — many include it in their browser extensions or desktop protection.
- Firefox: can disable WebRTC entirely — set
media.peerconnection.enabledto false inabout:config(breaks in-browser calls). - Chrome/Edge: can't fully disable it; use an extension like WebRTC Network Limiter, or rely on the VPN's protection.
- Brave: ships a built-in WebRTC IP handling policy setting.
- Safari: generally doesn't expose local addresses without permission — lower risk by default.
Modern browsers have also improved: local addresses are now typically obscured with mDNS names rather than raw IPs. But the VPN-bypass scenario still deserves a test — combine it with a DNS leak test for a complete privacy check.
Frequently asked questions
Should I disable WebRTC?
If you never make calls in the browser, disabling it (Firefox) or limiting it (extensions) is a reasonable hardening step. Otherwise, use a VPN with built-in WebRTC protection and verify with a leak test.
Does WebRTC leak my location too?
It leaks IP addresses; your real IP then gives away your approximate location through ordinary geolocation. Preventing the IP leak prevents the location exposure.