1. IP Leak

Your IP address is your unique online fingerprint. It's how websites and apps know where you are in the world.
When your VPN leaks your real IP, anyone—websites, trackers, advertisers, hackers, or government agencies—can pinpoint your location or track your activity. This usually happens if the VPN doesn’t fully mask all outgoing traffic or lacks proper DNS routing.

2. DNS Leak

Whenever you type a website address (like example.com), your device sends a request to a DNS (Domain Name System) server to look up the actual IP address of that site.

If your VPN fails to route DNS requests through its encrypted tunnel, your Internet Service Provider (ISP) can still see what websites you're visiting—even if the rest of your traffic is encrypted.
This is known as a DNS leak, and it's a common flaw in many free VPNs.

3. WebRTC Leak

WebRTC (Web Real-Time Communication) is a browser feature that enables voice calls, video chats, and file sharing directly in the browser—no plugin needed.
However, it can accidentally expose your real IP address, even if your VPN is working correctly. This is called a WebRTC leak, and it’s especially common in Chrome and Firefox browsers unless WebRTC is manually disabled or blocked.

Many users are unaware this risk even exists, making it a sneaky and dangerous vulnerability.

Whether it's your IP, DNS queries, or browser leaks, the bottom line is the same:

VPN leaks break the core promise of privacy.

They allow third parties—trackers, hackers, or government agencies—to access information you thought was protected. For people using VPNs to stay anonymous or bypass censorship, a single leak can have serious consequences.

What Causes a VPN to Leak?

1. Improper Configuration

Some VPN apps aren't properly set up for all devices or browsers.

2. Lack of Kill Switch

Without this feature, your real IP is exposed when the VPN disconnects.

3. Weak Protocols

Many free VPNs use outdated protocols (like PPTP), which are known to be insecure.

4. Hidden Business Models

If it’s free, you might be the product—some services sell user data or show targeted ads.

To uncover how often free VPNs leak user data compared to paid ones, we conducted a detailed and repeatable testing process. Each VPN was evaluated across different platforms using real-world tools, with a strong focus on identifying privacy risks such as IP leaks, DNS leaks, and WebRTC leaks.

We tested 20 VPNs in total—10 free and 10 paid—chosen based on popularity, user feedback, and app store rankings. All VPNs were tested under the same conditions to ensure fairness.

Operating Systems Tested:

• Windows 10

• macOS (latest version)

• Android 12+

• iOS 16+

Browsers Used:

• Google Chrome

• Mozilla Firefox

• Apple Safari

Each browser was tested using default settings without extensions or configurations that could interfere with leak detection.

We used vpntest.pro as our main leak testing platform because it provides fast, accurate, and publicly accessible results. The tool allowed us to detect the following:

• IP Leak Test
  Checked whether the VPN was properly hiding the user's real IP address and location. If the test revealed the user’s actual IP, the VPN failed.

• DNS Leak Test
  Verified whether DNS requests were being routed through the VPN’s servers or leaking back to the user's ISP. A proper VPN should mask DNS traffic completely.

• WebRTC Leak Test
  Determined whether the browser’s WebRTC feature was leaking the user's real IP, even while connected to a VPN—an issue especially common in Chrome and Firefox.

• Speed Test (Secondary Metric)
  We also recorded download and upload speeds while connected to the VPN to see how free vs. paid VPNs affected connection performance. While speed wasn't the main focus, it helped identify performance trade-offs in free services.

Testing Protocols Used:

• OpenVPN

• IKEv2/IPSec

• WireGuard (when supported)

Each VPN was tested using its most secure available protocol. If a VPN didn’t allow users to select or view the protocol, we noted it as a limitation.

Test Frequency and Locations:

• Each VPN was tested three times per platform (Windows, macOS, Android, iOS)

• Tests were conducted using VPN servers based in the US, UK, and Germany

• We repeated tests at different times of day to detect temporary leaks or inconsistencies

In total, we performed over 240 individual test runs. This helped us identify which VPNs consistently protected user data—and which ones failed under real-world conditions.

Our testing process was designed to simulate what an average user might experience: no browser tweaks, no advanced setups—just a VPN, turned on, and tested for leaks.

We tested 20 VPN services—10 free and 10 paid—to find out how often they leaked users' data. Here’s what we discovered from over 240 individual tests.

Leak Comparison Summary:

Key Findings:

• 7 out of 10 free VPNs failed to mask the user's real IP address.

• 6 free VPNs leaked DNS requests, revealing browsing activity to ISPs.

• Half of the free VPNs tested showed WebRTC leaks in major browsers like Chrome and Firefox.

• Paid VPNs performed significantly better, with only minor issues in WebRTC and DNS leak protection—and no IP leaks at all.

Best and Worst Performing VPNs

Worst-Performing Free VPNs (High Leak Risk)

• Hola VPN – Failed all major tests; monetizes user bandwidth through a peer-to-peer system, raising major privacy concerns.

• SuperVPN – Showed both DNS and IP leaks during testing; lacks transparency and has a vague privacy policy.

• Betternet – Consistent IP leaks across all platforms; relies on ad-based revenue and trackers.

Reliable Free VPNs (Leak-Free in Our Tests)

• ProtonVPN (Free version) – Passed all tests without leaks; based in Switzerland with strong data protection laws.

• Windscribe (Free tier) – No leaks detected; offers up to 10GB/month of free data with encrypted DNS and customizable security options.

Top Paid VPNs (Zero Leaks Detected)

• NordVPN

• ExpressVPN

• Mullvad

All three offered robust privacy features, including built-in kill switches, DNS leak protection, WebRTC shielding, and verified no-log policies. They passed every test on all platforms.

Even a single leak can expose critical personal data, such as:

• Your real IP address and physical location

• Your full browsing activity, visible to your ISP or network administrator

• Sensitive communications, if the VPN drops and your connection isn’t blocked automatically

For journalists, activists, business professionals, or anyone relying on anonymity, these leaks can lead to tracking, censorship, or even legal risks—especially in high-surveillance regions.

Are Free VPNs Ever Safe to Use?

In some limited scenarios, yes—but with serious limitations.

A free VPN may be suitable if:

• You’re only accessing general websites or streaming content

• You’re not transmitting personal, financial, or work-related data

• The provider is reputable and has a proven record of no leaks, no ads, and a strict no-logs policy

ProtonVPN and Windscribe are two of the few free VPNs that passed all leak tests. However, even these have usage limits and fewer security features than their paid counterparts.

Avoid using free VPNs for sensitive tasks like:

• Online banking or financial transactions

• Messaging and calls requiring confidentiality

• Accessing censored or high-risk content in restrictive countries

How to Choose a Leak-Proof VPN

If you want serious privacy protection, your VPN should include:

• Full protection against DNS, IP, and WebRTC leaks

• A strict no-logs policy, audited or clearly stated

• Support for modern encryption protocols like OpenVPN or WireGuard

• A kill switch that blocks internet traffic if the VPN disconnects

• Regular updates and reliable customer support

Free VPNs rarely offer all of these. Paid services are far more likely to meet these standards.

The data speaks for itself: Free VPNs leak more—and put your privacy at risk.

While a free VPN may seem like an easy solution, it often comes with major compromises in security, transparency, and performance. In contrast, the paid VPNs we tested delivered consistent, leak-free protection across every platform.

If your privacy, identity, or data matters to you, investing in a reliable VPN is worth it. The cost of a poor VPN isn’t just bad performance—it’s your personal information exposed to the world.

1. Are all free VPNs dangerous?

Not all, but most free VPNs compromise on security or privacy. Some even log your data or serve ads with trackers.

2. Can free VPNs protect against hackers?

Not reliably. Many lack proper encryption or leak protection, making them ineffective against skilled attackers.

3. How do I know if my VPN is leaking?

Use leak test sites like vpntest.pro Check if your real IP or DNS provider is still visible.

4. Are VPN browser extensions safe?

Often not. Many act as proxies, not full VPNs. They rarely encrypt DNS and are more prone to WebRTC leaks.

5. What’s a kill switch, and why does it matter?

A kill switch blocks all traffic if your VPN disconnects, preventing your real IP from being exposed. Most free VPNs don’t have this feature.

6. Is it worth paying for a VPN?

Absolutely—if you value privacy. Paid VPNs offer stronger encryption, full leak protection, and customer support.