3 Out of 10 Free VPNs We Tested Leaked Your Real IP Address Via WebRTC
We ran our WebRTC Leak Test against the 10 most popular free VPNs. The results were worse than we expected: 3 leaked your real IP address despite the VPN being "connected", 2 more leaked DNS queries, and browser extension VPNs performed even worse than desktop apps. Only 5 passed both tests completely.
Here's every result, with the exact failure modes explained.
What Is a WebRTC Leak and Why Does It Matter?
WebRTC (Web Real-Time Communication) is a browser technology used for video calls, file sharing, and peer-to-peer communication. The problem: it can bypass your VPN entirely and reveal your real IP address to any website that requests it — even when your VPN shows you're "connected" and "protected."
This isn't a VPN bug. It's a browser feature. WebRTC communicates directly with STUN servers to discover your local and public IP addresses, and many VPNs simply don't intercept this traffic.
The practical risk: any website can run a WebRTC check in the background and log your real IP, defeating the entire purpose of your VPN. Sites do this routinely for fraud detection, geo-enforcement, and tracking.
Our Test Methodology
We connected each free VPN service, confirmed it showed as "connected," then ran our WebRTC Leak Test tool to check:
- Whether the real IP address was exposed via WebRTC STUN requests
- Whether DNS queries were leaking outside the VPN tunnel
- Both desktop app and browser extension versions (where available)
Tests were run on Chrome on Windows 11. Each VPN was tested 5 times with 5-minute gaps between tests.
Full Results: 10 Free VPNs Tested
| VPN Service | WebRTC Leak | DNS Leak | Overall |
|---|---|---|---|
| ProtonVPN Free | ✅ No leak | ✅ No leak | PASS |
| Windscribe Free (10GB) | ✅ No leak | ✅ No leak | PASS |
| Mullvad (trial) | ✅ No leak | ✅ No leak | PASS |
| WARP by Cloudflare | ✅ No leak | ✅ No leak | PASS |
| TunnelBear Free | ✅ No leak | ✅ No leak | PASS |
| Hotspot Shield Free | ❌ Real IP exposed | ✅ No leak | FAIL |
| Hide.me Free | ❌ Real IP exposed | ❌ DNS leaking | FAIL |
| Betternet Free | ❌ Real IP exposed | ❌ DNS leaking | FAIL |
| VPN Gate (random server) | ✅ No leak | ❌ DNS leaking | PARTIAL |
| Urban VPN | ✅ No leak | ❌ DNS leaking | PARTIAL |
Summary: 3/10 leaked real IP via WebRTC. 4/10 had DNS leaks. Only 5/10 passed both tests cleanly.
Browser Extension VPNs Are Far Worse
We also tested browser extension versions of the same VPNs where available. The results were significantly worse: 6 out of 8 browser extension VPNs leaked via WebRTC.
The reason: browser extensions can only proxy HTTP/HTTPS traffic. They have no control over WebRTC, which operates at a lower level and uses UDP directly. Even extensions marketed as "full VPN protection" are essentially just proxies for your browser tabs — not true VPN tunnels.
If you're using a browser extension VPN (the free ones from the Chrome Web Store), assume your real IP is visible to any site that checks.
How to Check If Your VPN Is Leaking Right Now
Don't trust your VPN's "connected" indicator. Test it yourself:
- Connect your VPN and make sure it shows as active
- Go to anonymiz.com/webrtc-leak-test
- Check if the IP shown matches your VPN's IP — or your real home IP
- If you see your real IP, your VPN is leaking
The test takes under 10 seconds and requires no account or signup.
3 Fixes If Your VPN Is Leaking
Fix 1 — Disable WebRTC in your browser. In Firefox: go to about:config and set media.peerconnection.enabled to false. In Chrome, you need an extension like uBlock Origin with the WebRTC blocking option enabled. This prevents all WebRTC connections, which may break video calls.
Fix 2 — Switch to a VPN with proper WebRTC leak protection. Our tests showed ProtonVPN Free, Windscribe, and Mullvad all handle this correctly. These VPNs intercept WebRTC at the OS level rather than just the browser.
Fix 3 — Stop using browser extension VPNs for privacy. They are proxies, not VPNs. If privacy matters, install the full desktop application.
The Bottom Line
30% of popular free VPNs leak your real IP address despite showing as "connected." Most people never check this because their VPN shows a green checkmark. The checkmark only means the tunnel is connected — it says nothing about WebRTC leaks.
Run the test. It's free: anonymiz.com/webrtc-leak-test
