What Are IP Leaks And How Can You Prevent Them? (2024)

An IP leak is when your real IP address should be hidden from the rest of the internet but is instead revealed to other internet users.

This happens when your Virtual Private Network (VPN) provider doesn’t properly keep your real IP address hidden.

When you’re using a VPN, you connect to a VPN server, which temporarily assigns a fresh IP address to your connected device. This hides your actual IP address, helping to ensure that no one can identify you or your geographical location.

VPNs also use their own DNS servers, so third parties cannot see your DNS requests. This keeps your online antics incognito, preventing any online tracking that another party might attempt.

Okay, that’s how everything is supposed to work – but, occasionally things go wrong, and your IP address or the IP addresses of your DNS servers are exposed, even though you’re connected to a VPN server.

When this happens, you have an IP leak.

In this article, we’ll take a look at:

• What an IP address is
• The most common type of IP address leaks
• What causes those IP address leaks, and
• How you can take steps to prevent them.

Before I begin, allow me to note that by using a top-notch VPN provider, you’ll help prevent IP leaks. If you find that your VPN provider is leaking your real IP address (by following the steps I’ll lay out later), I strongly urge you to change your VPN provider as soon as possible to a more reliable one, like NordVPN.

What Is an IP Address and How Does It Work?

An IP address acts as a unique identifier for a device connected to any network. (The internet is simply a HUGE network.) An IP address works like your home’s postal address. It not only uniquely identifies a device, it can also be used to identify a device’s geographical location.

Any device that’s connected to your home network actually has two IP addresses, a private IP address and public IP address.

This means that your computer, smartphone, smart TV, gaming console and Internet of Things device each have a private IP address, which they use to communicate with each other over your home network.

Your router is what assigns these internal (or private) IP addresses to these devices. These IP addresses are usually in the 192.168.X.X, 172.16.X.X, or 10.X.X.X format.

In addition to the internal IP address, each device on your home network shares a public IP address that is used to communicate with other devices on the internet.

Your Internet Service Provider (ISP) is what assigns this IP address to your devices. It is shared by all of your connected devices to communicate on the internet.

Your home router is assigned the public IP address, and then uses its own routing capabilities to keep track of which of your devices made an information request, and which device the reply should be routed to.

When you’re connected to a VPN server, your actual IP address is hidden, and you use a new IP address, which is the public IP address of the VPN server you’re connected to. This makes it appear as if you are connecting from the same geographical location as the VPN server.

This hides both your real IP address and your actual physical location, providing anonymity for your online activities.

IP Address Formats

There are two formats for both public and private IP addresses: IPv4 and IPv6 addresses.

An IPv4 address is made up of four numbers (0-255) separated by periods. An IPv4 address looks like this:

192.168.22.3

An IPv6 address is made up of eight groups of four hexadecimal digits, with each group separated by colons. An IPv6 address looks something like this:

2002:0de6:0001:0084:0100:9c4e:0390:7244

IPv6 IP addresses were developed because the world is running out of IPv4 addresses. ISPs are slowly making the transition to IPv6.

While most ISPs continue to use IPv4 addresses for now, they are laying the groundwork to use IPv6 addresses in the future.

No matter which format your network or ISP uses, your online privacy is at risk if your real IP address is leaking.

How Do I Test for IP Leaks?

Testing for IP leaks is as easy as pie.

While there are plenty of IP leak testing websites, I usually visit ipleak.net. The site is easy to use and will quickly check your VPN connection for IP leaks.

Visit the site first without being connected to your VPN provider’s servers, then connect to your VPN and visit the site again. Compare the results from these two tests.

If any IP addresses that were on the list during the first (no-VPN) test still appear on the list when you try again (with a VPN connection), then you have an IP leak.

The site will display your detected IPv4, IPv6, DNS and WebRTC addresses. If any of the addresses in the no-VPN test match the results of the VPN-connected test, you have an IP address leak.

IPv6 Leaks

The majority of internet-connected devices still use IPv4 addresses. Therefore, most VPN providers do not yet support IPv6.

This means that if you are one of the small number of users that do use IPv6, your IPv6 address could leak, putting your masked IPv4 address at risk of exposure.

You see, if your VPN doesn’t support IPv6 addressing or doesn’t know how to block IPv6 requests, then requests sent to or from your device via IPv6 will jump outside the VPN’s encrypted tunnel, leaking information for anyone to see.

A quality VPN should fully support IPv6, tunneling all IPv6 traffic through the VPN, or it should completely disable IPv6 traffic at the system level.

How to Prevent IPv6 Links

To ensure that you aren’t the victim of an IPv6 leak, do the following:

• Opt for a VPN service that either offers support to tunnel IPv6 traffic, or select a VPN provider that offers an app that provides IPv6 leak protection.
• Manually disable IPv6 on your device.

DNS Leaks

As you may recall, I previously mentioned DNS servers. DNS stands for “Domain Name System.”

A DNS server translates the name of a website (“amazon.com,” “facebook.com,” etc.) into the proper IP address so that you can connect to the proper website.

What this means is that anyone that has the proper access can view your DNS records, allowing them to see your entire browsing history.

When you subscribe to a VPN, check to make sure that the provider offers its own DNS servers. This keeps all of your online activities inside the protected VPN tunnel.

DNS leaks can happen for various reasons, including:

• The VPN client is poorly developed, so it doesn’t route DNS requests properly or it fails to account for IPv6 DNS servers.
• A third-party client app (such as the OpenVPN app) has a misconfigured DNS.
• The device’s operating system doesn’t properly route DNS requests through the VPN.
• The VPN uses the device’s DNS servers instead of its own.

How to Prevent DNS Leaks

To ensure that you aren’t the victim of a DNS leak, do the following:

• Select a VPN provider that offers DNS leak protection by routing your DNS requests to the provider’s own DNS servers.
• Check your VPN for DNS leaks by testing with this handy DNS Leak Testing site.
• Disable IPv6 manually on your computer.
• Manually change your device’s DNS server settings to use your VPN provider’s DNS servers. This won’t actually fix the DNS leak, but at least the leak’s information will be going to your VPN provider and not to your Internet Service Provider.

WebRTC Leaks

WebRTC is an open-source project that allows real-time peer-to-peer voice and video communications in modern web browsers without the need for plugins or downloading apps.

Most web browsers support WebRTC, including Chrome, Firefox, Edge, Opera, Safari and other browsers.

Unfortunately, even if you’re connected to a VPN, visiting a WebRTC-enabled website can lead to the transmission of data outside of the VPN’s tunnel. This can reveal your real IP address, which basically defeats the privacy advantages that the VPN offers.

If a poorly-designed VPN client fails to properly address WebRTC leaks on IPv4 and IPv6, WebRTC leaks will occur.

How To Prevent WebRTC Leaks

To prevent WebRTC leaks, you’ll want to use a VPN service that prevents WebRTC leaks. (Check with the customer service folks at the VPN you’re considering, or search for “WebRTC” in the provider’s support library.)

You can also manually disable WebRTC in your browser. IPLeak.net offers a guide that tells you how to do it in Firefox, Chrome and Opera.

Network Disruptions and VPN Disconnections

There are other situations where your IP address might leak.

If your VPN connection drops or some other type of network disconnect occurs, your VPN could start leaking your IP address or completely stop protecting your connection.

This can be especially concerning for people who share files via P2P.

Downloading a large file can take a long period of time, meaning many torrenters leave their file sharing apps running unattended while waiting for downloads to finish up.

If your VPN connection drops while sharing files, it could be leaking your IP address for long periods of time, meaning your ISP could possibly detect it.

A VPN disconnection can also occur on mobile devices.

This can happen when you’re switching between a WiFi connection and a cellular connection. If your VPN app can’t handle such a disruption, your IP address could leak and your online activities are open to being monitored. Even a disconnect of only a few moments can cause privacy-related havoc.

I can just hear some of my readers say, “but, isn’t that what a kill switch is for?”

“Yes,” I reply. “That is true. But…” (And, isn’t there always a “but”?)

While a kill switch is designed to kill your internet connection if your device loses connection to the VPN’s servers, a poorly-implemented kill switch can leave you open to IP leaks if it has to deal with a temporary connection disruption.

If your VPN kill switch doesn’t work properly, a momentary connection disruption could leave the VPN enabled, but in a misconfigured state that leaks data.

Be sure to periodically check your VPN connection for leaks. A quick visit to IPLeaks, and you’ll be able to tell whether or not your VPN is leaking data. If you see any leaks, change VPN providers.

How to Prevent VPN Network Disruption Leaks

To prevent VPN network disruption leaks, do the following.

• Choose a VPN provider that offers apps that include a kill switch option. Be sure to enable the kill switch feature in the app’s settings.
• Test your VPN connection for leaks on a regular basis. Switch providers if you see leaks.
• Users with networking knowledge can set up an outgoing firewall on their system that they can use as a kill switch of sorts. However, doing this is beyond the scope of this article.

What Are IP Leaks FAQs

In Closing

An IP leak defeats one of the main purposes of using a VPN, which is to hide your real IP address and thus hide your real geographical location.

Always make sure your VPN does a reliable job of hiding your ISP-provided IP address from the rest of the network. Subscribe to a reliable VPN (like NordVPN) and test the VPN on a regular basis.