Is Your VPN Leaking? How to Check for DNS and IP Leaks

A VPN is supposed to hide your real IP address and encrypt your traffic. Most of the time it does. But a VPN can fail without any warning sign: the app says "connected" while some of your information still travels outside the tunnel. This is called a leak. The good news is that checking for leaks takes about ten minutes and needs no special skills.

What a leak actually means

When you connect to a VPN, your device should send its traffic through an encrypted tunnel to the VPN server. A leak happens when something escapes that tunnel and reveals your real location or activity. There are three common kinds.

IP leak

Websites see your real public IP address instead of the VPN server address. This can happen if the connection drops and your device quietly falls back to the normal route.

DNS leak

DNS is the system that turns names like example.com into addresses. If your device still sends those lookups to your internet provider, they can see which sites you visit even though the content is encrypted.

WebRTC leak

WebRTC is a browser feature used for video calls and similar tools. In some browser setups it can expose your real IP address to a website even when a VPN is active.

A fourth case is IPv6. If the VPN handles only IPv4 traffic but your network also uses IPv6, requests over IPv6 may bypass the tunnel.

Before you test: set a baseline

1. Disconnect from the VPN completely.
2. Search for "what is my IP" and note the address and the location shown. This is your real, unprotected address.
3. Close that page, then connect to the VPN and wait until the app reports a stable connection.

You need this baseline because a leak test is simply a comparison: with the VPN on, you should not see any of your baseline details.

Step-by-step leak check

1. Check your IP address

With the VPN connected, open an IP lookup page. The address and location should match the VPN server you selected, not your baseline. If your real address appears, you have an IP leak.

2. Run a DNS leak test

Use a reputable online DNS leak test and choose the extended version if offered. It lists the DNS servers answering your requests. Compare them with your baseline. If you see servers belonging to your own internet provider, or your home country when you chose a foreign server, your DNS is leaking. Seeing the VPN provider or a neutral public resolver is a good sign.

3. Test for WebRTC leaks

Open a WebRTC leak test page in the browser you normally use. It shows any IP addresses the browser exposes. Local addresses that begin with 192.168 or 10 are private network addresses and are not a problem. A public address that matches your baseline is.

4. Check IPv6

Many test pages show both an IPv4 and an IPv6 result. If an IPv6 address appears and it belongs to your provider, the VPN is not covering IPv6.

5. Test a connection drop

This one reveals whether your protective features really work. While connected, temporarily switch Wi-Fi off and on, or move to another network, then reload an IP lookup page right away. If your real address flashes up before the VPN reconnects, you need a kill switch.

Reading the results

How to fix common leaks

• Turn on the kill switch: this blocks internet access whenever the VPN disconnects, so nothing travels unprotected.
• Enable leak protection in the app: many VPN apps have DNS and IPv6 protection options that are worth checking in the settings.
• Change the protocol: try a different connection protocol in the app if leaks appear with one of them.
• Set DNS manually: in your device network settings, use the DNS servers of your VPN provider, or a trusted resolver, instead of automatic ones.
• Restrict WebRTC: some browsers let you disable it in advanced settings, and extensions can block it. Be aware that doing so may affect video calling sites.
• Disable IPv6: if your VPN does not support it, switching it off in the network adapter settings closes that gap.
• Update the app: older versions may have bugs that have since been fixed.
• Check split tunneling: if you excluded certain apps or sites, they will naturally show your real address.

How often should you check?

Test when you first install a VPN, after major operating system or app updates, when you change networks or devices, and whenever something seems off. Also try each device separately, since a phone and a laptop can behave differently even with the same account.

Limits of leak tests

Passing a leak test shows that your IP and DNS are not exposed in that moment. It does not prove that the VPN provider itself is trustworthy, that it keeps no logs, or that you cannot be identified by other means such as accounts you are logged into or browser fingerprinting. A VPN is one privacy tool, not a complete shield.

Frequently asked questions

Can a free VPN leak more often?

It can, because some free services lack features like a kill switch or DNS protection. That is not guaranteed either way, so the best approach is to test whatever service you use.

Do leak test websites store my data?

They necessarily see your IP address to run the test. Choose well-known tools and read their privacy statement if that concerns you.

Why does the DNS test show a different country than the VPN server?

DNS servers do not always sit in the same place as the VPN exit. What matters is whether the listed servers belong to your internet provider or to the VPN or a neutral resolver.

Is a router-level VPN safer from leaks?

It can help cover every device at once, but it can still leak if misconfigured, so test from a connected device.

Conclusion

Checking your VPN takes minutes: note your real IP, connect, then test for IP, DNS, WebRTC and IPv6 leaks, and simulate a dropped connection. If anything exposes you, switch on the kill switch and leak protections, adjust DNS or browser settings, and test again. Make this a routine and you will know your VPN is doing the job you are paying it for.