DEV Community: ExamineIP

WebRTC Leak Test: What It Is and How to Fix It

ExamineIP — Mon, 04 May 2026 13:57:34 +0000

A WebRTC leak exposes your real IP address to websites even when you're connected to a VPN. Use the free test below to find out if your browser is leaking right now — then follow the steps to fix it.

Run the Free WebRTC Leak Test →

What Is WebRTC?

WebRTC (Web Real-Time Communication) is a technology built directly into modern browsers — Chrome, Firefox, Edge, Safari, and Opera all include it. It was designed to enable peer-to-peer features like video calls, voice chat, and file sharing without needing a plugin or app.

Unlike regular web traffic that routes through your browser's HTTP connection, WebRTC establishes direct communication channels between devices. That's what makes it fast for video calls — and what makes it a serious privacy risk if you use a VPN.

What Is a WebRTC Leak?

A WebRTC leak happens when your browser uses WebRTC's peer-to-peer connection mechanism to reveal your real IP address — including your local network IP and your public IP — to websites, even if you're behind a VPN.

When you connect to a VPN, all your traffic is supposed to route through the VPN server. Your real IP should be hidden. But because WebRTC operates at the browser level and bypasses your normal network stack, it can communicate your device's true IP directly to any site that requests it.

The result: a site can see both your VPN's IP and your real one — defeating the entire purpose of using a VPN.

This isn't a bug in any one browser or VPN. It's a structural behavior of how WebRTC works, and it affects nearly every major browser by default.

How Does a WebRTC Leak Expose Your IP?

To establish a peer-to-peer connection, WebRTC uses a protocol called ICE (Interactive Connectivity Establishment). As part of this process, it collects what are called ICE candidates — a list of all possible network paths between devices.

This list includes:

Your local IP address (e.g., 192.168.1.x) — assigned by your router
Your public IP address — your real IP as seen by the internet
STUN server responses — a third-party server confirms your public IP to help establish the connection

When a website embeds a small JavaScript request, your browser responds with these ICE candidates — even if you never actually make a video call. The site receives your real public IP before you click anything.

VPNs intercept traffic at the network layer, but this ICE candidate exchange happens inside the browser's own runtime, outside the scope of what most VPN clients intercept.

Who Is at Risk?

You are potentially at risk if you:

Use a VPN for privacy and connect through Chrome, Firefox, or Edge
Use a browser extension VPN (these are especially vulnerable)
Access geo-restricted content and need your real location hidden
Work remotely and connect to internal resources over VPN

How to Test for a WebRTC Leak

Testing takes under 30 seconds.

Step 1: Note your real IP without VPN

Go to the VPN leak test tool without your VPN connected. Note the public IP shown.

Step 2: Connect to your VPN

Enable your VPN and wait for it to confirm the connection.

Step 3: Run the test again

Reload the leak test page and compare results.

Result	What it means
Only your VPN's IP is shown	No leak — you're protected
Your real IP appears alongside the VPN IP	Active WebRTC leak
A local IP (192.168.x.x) appears	Minor local IP exposure
No IP shown at all	WebRTC is disabled

How to Fix a WebRTC Leak

Fix 1: Use a VPN That Blocks WebRTC at the Client Level

Full desktop VPN clients operate at the OS network driver level and intercept all outgoing traffic including WebRTC's UDP packets. Browser extension VPNs do not.

Recommended options: PureVPN, IPVanish, Surfshark

After switching, re-run the leak test to confirm.

Fix 2: Disable WebRTC in Your Browser

Firefox

Type about:config in the address bar
Search for media.peerconnection.enabled
Double-click to set it to false
Restart Firefox

Chrome

Use the uBlock Origin extension → Settings → Advanced → enable Prevent WebRTC from leaking local IP addresses

Edge

Go to edge://flags
Search for Anonymize local IPs exposed by WebRTC
Set to Enabled and relaunch

Brave

Go to brave://settings/privacy
Set WebRTC IP Handling Policy to Disable Non-Proxied UDP

Disabling WebRTC will break Google Meet, Discord web, and Zoom web. If you need those, use Fix 1 instead.

Fix 3: Switch to a Privacy-Focused Browser

Brave — restricts WebRTC IP exposure natively
Firefox — supports full WebRTC disabling via about:config
Tor Browser — disables WebRTC entirely by default

WebRTC Leaks vs. DNS Leaks

	WebRTC Leak	DNS Leak
What leaks	Your real IP address	Your DNS queries
Who can see it	Any site with JavaScript	Your ISP
How to test	WebRTC leak test	DNS leak test

Summary

Fastest fix: uBlock Origin in Chrome
Most reliable fix: Switch to a full desktop VPN — PureVPN, IPVanish, or Surfshark
Most thorough fix: Disable WebRTC in browser settings

Always verify after making changes. Run the free WebRTC leak test to confirm — it takes 10 seconds.

Originally published at examineip.com

I Tested 47 VPN Services Over 6 Months. 40% Failed Basic Security Tests.

ExamineIP — Sat, 25 Apr 2026 08:31:26 +0000

I spent 6 months building VPN/proxy security testing tools and analyzing 47 commercial services. The results were eye-opening.

Testing Methodology

Packet capture analysis (Wireshark on public WiFi)
DNS leak detection
WebRTC STUN leak testing
IPv6 leak detection
Kill switch verification
IP rotation monitoring

Results

47 services tested:

31 VPNs (22 passed, 9 failed)
16 proxy services (6 premium passed, 10 free proxies all failed)
Overall failure rate: 40%

Key Findings

VPN Failures (9 out of 31)

The most common failure modes:

DNS leaks during kill switch engagement
WebRTC STUN bypassing VPN tunnel
IPv6 traffic not routed through VPN tunnel
Kill switch race condition (leaked real IP during connection handshake)

Free Proxies (100% Failure Rate)

All 10 free proxy services tested failed security tests:

Zero encryption
30% actively performed MITM with script injection
10% performed DNS hijacking for ad injection
All logged traffic without disclosure

Most shocking: 3 free proxy services actively injected advertising scripts into HTTPS traffic. One redirected Google searches to a spam search engine.

Premium Proxy Services

All 6 premium services passed for their intended use case:

Not designed for privacy/anonymity
Appropriate for web scraping, geo-testing, automation
Should not be marketed as privacy tools

The "Military-Grade Encryption" Myth

The "military-grade encryption" marketing claim is technically meaningless. AES-256 is industry standard across financial services, password managers, and messaging apps.

The actual security differentiator is leak prevention architecture, not encryption strength.

Most Critical Finding

Kill switch implementation varies significantly. Several VPNs leaked real IP during the connection establishment phase before the kill switch engaged, creating a 2-3 second window of exposure.

When to Use What

Use a VPN when:

Privacy and security are the priority
Public WiFi (cafés, airports, hotels)
Handling sensitive data
Countries with internet censorship
Torrenting or P2P file sharing

Use Premium Proxies when:

Web scraping and data collection at scale
Automation and bot operations
Geographic testing and localization
Speed matters more than encryption

Never use free proxies. Ever.

Testing Tools

I built a free VPN leak testing tool: examineip.com/vpn-leak-test

Tests for:

DNS leaks
WebRTC leaks
IPv6 leaks
Real-time IP verification

Full Technical Analysis

Read the complete writeup with detailed methodology and findings: I Tested My VPN on Public WiFi and Discovered It Wasn't Actually Protecting Me

Originally published on Medium. Cross-posted to DEV.to to reach the developer community.

Happy to answer questions about the testing methodology or specific findings in the comments!

I built a simple IP checker tool

ExamineIP — Wed, 25 Mar 2026 17:09:43 +0000

I’ve been working on a simple IP checker that shows your IP address, location, ISP, and browser info.

The idea was to keep it clean and easy to understand, especially for beginners who want to know what their IP actually reveals.

While building it, I also realized how confusing the basics of the internet can be for most people — things like DNS, servers, and how a page actually loads.

So I wrote a simple breakdown explaining how websites actually work, step by step.

If you're curious, you can check it here:
https://examineip.com/how-websites-actually-work-simple-explanation-for-beginners/

And here’s the tool itself:
https://tools.examineip.com/

Would love feedback or suggestions on what to improve.