Using a VPN provider without a verified, no-logs policy puts your web traffic at risk of privacy leaks. While unblocking sites might be your main concern, getting your IP address and personal data exposed undermines the very purpose of a VPN. Testing your VPN for leaks keeps you several steps ahead of cybercriminals. Here’s how to do it.
1. IP Address Leaks
A VPN’s primary function is to mask your IP address and replace it with one from a VPN server. If your VPN provider fails to fulfill this basic task and there are IP address leaks at any level, you must switch to a more reliable VPN provider.
There are several effective methods to test your VPN provider for IP address leaks. You can utilize a terminal window, such as Command Prompt, a specialized tool like Wireshark, or BrowserLeaks’ IP address checker. Our guide comprehensively covers these techniques and demonstrates how to test a VPN for its encryption.
We recommend Wireshark for its comprehensive analysis of your Wi-Fi address, testing the VPN server’s IP address multiple times. Any leaks will be visible. In the example, TCP retransmissions indicate network congestion. We have previously covered why slow Wi-Fi networks must be avoided where possible to avoid data leaks.
2. DNS Leaks
DNS leaks are some of the most common VPN leaks. In a DNS leak, your primary connection goes through your VPN like it should, but the DNS connection still goes to your ISP’s servers. Because your DNS reveals where you’re going and where you’re located, DNS leaks effectively render your VPN useless.
If your DNS requests are leaking despite using a VPN, your connection becomes vulnerable to various cyberattacks. Malicious websites can exploit DNS spoofing to trick you into revealing personal information. Additionally, streaming sites can easily geoblock you, as your DNS requests do not match that of a regular user, despite having a different IP address.
The first and most obvious place to test your VPN is DNSLeakTest. It’s a site that’s designed to ensure that your DNS connection isn’t connecting to any servers outside your VPN.
Run the extended test on above link. When you first arrive, you’ll see a message telling you where you’re located and showing you a map. If that location isn’t where your VPN server is located, something is definitely wrong. Hopefully, it is your server location, and you can keep going..
As the test runs through, it will try to find DNS servers that you’re using. When it completes, you’ll see the servers listed. In a successful test, you’ll only see your VPN’s DNS server.
BrowserLeaks’ DNS test provides a comprehensive evaluation by using 50 randomly generated domain names, evenly divided between IPv4 and IPv6 addresses. The goal is to identify any potential DNS requests sent directly to your ISP server instead of your VPN server. In the above example, the VPN leak test did not show any DNS exposure.
Related: are you worried about DNS leaks? We have the solutions to fix the issue.
3. WebRTC Leaks
A browser serves as the gateway to our online activities and is also the primary source of data leaks. One such leak, known as WebRTC (Web Real-Time Communication), can inadvertently expose your IP address through browsers. Only a robust VPN provider with strong encryption can prevent WebRTC leaks.
Leading VPN providers like ExpressVPN, Surfshark, and NordVPN offer comprehensive WebRTC leak test tools on their homepages. However, if you’re not using their services, the test may indicate that your real IP address is exposed. While these tools are widely used, they should not be solely relied upon for assessing WebRTC protection.
Instead of using VPN provider websites, opt for BrowserLeak’s comprehensive WebRTC test tool. A green check mark will confirm that your IP address hasn’t been leaked via your browser, ensuring your connection’s security.
BrowserScan is another site that takes audio and video requests from a browser on your device to do a more thorough evaluation of possible WebRTC leaks. It runs VPN leak tests on Google, Cloudflare, Twilio, NextCloud, and many other servers. If the final result says: “no public IP leaks,” your VPN is not leaking your personal information via a browser.
Also read: most VPNs are not created equal. Do not fall for these common VPN myths such as total “anonymity.” Some of the best ones may not be as secure as you think.
4. VPN Kill Switch Leaks
A VPN’s kill switch is the most reliable way to ensure your real web traffic data remains secure if the VPN connection fails. Most VPN providers offer kill switches for such emergencies. However, the effectiveness of these kill switches can only be determined by using a kill switch leak detection tool that simulate VPN disconnection in real time.
Currently, there are few online tools that comprehensively test and detect privacy leaks due to connection drops. However, ZeroMarks, a VPN provider, offers a kill switch checker in its security toolbox. By clicking ‘Start,’ it verifies if the kill switch properly blocks Internet access. If the IP address provided by the VPN remains unchanged, it indicates that the kill switch is functioning correctly.
5. Split Tunneling Leaks
When using the split tunneling feature of a VPN, you can redirect specific apps or websites to bypass the VPN tunnel. First, you need to specify which ones should use split tunneling and which ones should bypass it entirely. Testing for split tunneling leaks ensures that applications or websites that shouldn’t use the VPN are indeed bypassing it as intended.
To run this leak test, first check your current IP address. Next, enable the split tunneling feature for specific apps or websites. Then, activate a VPN server and ensure all your web traffic is directed through it. If, while using an app or website designated to bypass the VPN, you detect the same IP address as the VPN server’s, it indicates that the split tunneling feature is not functioning properly.
6. Torrent Leaks
Finally, if you use your VPN for torrents, you want to make sure that you’re constantly protected. None of these tests specifically target torrenting. There is a great tool for torrents that actually interacts with your torrent client using an actual torrent link, while you’re allowing VPN usage.
The tool is called BashWS, and it provides you with a torrent link that you can paste into your torrent client. Allow it to run for a while. It’ll update automatically in your browser to reflect what’s happening in your client. You should only see your VPN IP listed in the results table.
We have seen all the different ways to test VPN leak for your providers. By using these valuable tools and tests, you can ensure that your VPN is working as intended, and your information is secure. Check out some of these best VPN apps for Android and iPhone.
Image Credit: Virtual private network by DepositPhotos. All screenshots by Sayak Boral.
