MyIPInfo

A lot of people assume that turning on a VPN is enough. In reality, VPNs can silently leak your real IP in three different ways. Worse, these leaks usually happen without warning — the VPN client still says “Connected” while some of your traffic is going out through your real ISP.

Why VPNs Leak in the First Place

A VPN works by building an encrypted tunnel and routing your traffic through it. But:

  • Not all traffic goes through the tunnel by default (older VPN protocols, certain OS-level services, and special browser features can bypass it)
  • The tunnel can drop for a fraction of a second without you noticing
  • Domain name lookups (DNS) may not go through the VPN, letting your ISP see which sites you visit

The three leak types below correspond to these three problems.

The Three Common Leak Types

1. IP Leak (the tunnel dropped)

When the VPN connection breaks for any reason, some applications immediately reconnect using your real IP. This is called an IP leak. Cheap VPNs without a “kill switch” expose your real IP to every site you’re currently using the moment the connection blips.

The most common triggers:

  • Switching WiFi networks
  • Device waking from sleep before the VPN reconnects
  • Weak mobile signal causing frequent VPN drops
  • VPN client crashing while the browser keeps going

How to detect: Open MyIPInfo while the VPN is connected. If the IP shown belongs to your real ISP, the VPN isn’t actually routing your traffic. You can also manually disconnect the VPN for one second and reconnect, then refresh — see if your real IP briefly flashes.

2. DNS Leak (your lookups went through the ISP)

Even if the VPN hides your IP, DNS requests (domain name lookups) can still go through your local ISP. The result: the websites you visit don’t see your real IP, but your ISP sees every domain you visit. For privacy purposes, that’s a half-leak.

Common causes of DNS leaks:

  • Windows “Smart Multi-Homed Name Resolution” preferring local DNS
  • Router configured with hardcoded ISP DNS servers
  • Browser configured with DNS-over-HTTPS that the VPN doesn’t know about

How to detect: Run the DNS leak checker on this site. Check whether the DNS servers belong to your VPN provider (Cloudflare, NordVPN’s own DNS, etc.) or to your local ISP (Comcast, BT, etc.).

3. WebRTC Leak (the browser bypassed the VPN)

The WebRTC feature built into browsers (the technology behind video calls and screen sharing) can communicate directly with the other side, bypassing the VPN and exposing your real IP. This is the most-missed leak for Chrome / Firefox / Edge users because it happens at the browser level — the VPN client has no idea.

How to detect: Run the WebRTC leak test on this site. If it shows your real IP, you have a leak. If it shows the VPN’s IP (or no IP at all), you’re fine.

How to Prevent Leaks

  1. Use a VPN with a Kill Switch — drops all network access if the VPN disconnects, rather than letting traffic escape
  2. Choose a VPN that does DNS-over-VPN — DNS queries also go through the encrypted tunnel, so the ISP sees nothing
  3. Disable WebRTC in the browser or install extensions like “WebRTC Leak Prevent” or “uBlock Origin”
  4. Re-verify with this site’s tools after every VPN update and every OS update
  5. Avoid free VPNs — most log traffic and sell it to advertisers; security can’t be assumed

Complete Self-Check Routine

1. Without VPN: open MyIPInfo, note your real IP and ISP
2. Turn on the VPN, wait until the client shows "Connected"
3. Refresh MyIPInfo — the IP should now be the VPN server's IP
4. Run the DNS leak checker — DNS servers should belong to the VPN provider, not your ISP
5. Run the WebRTC checker — your real IP should NOT appear
6. Disconnect WiFi and reconnect; repeat steps 3-5 — confirm the Kill Switch actually held

If any step shows your real IP or your real ISP’s DNS, the VPN is not trustworthy in that scenario. Fix the configuration (or switch tools) before using it for anything that actually matters.

Closing Thought

A VPN is not a “set it and forget it” tool. It’s a system that needs to be verified and maintained. Make “turn on the VPN” a habit; make “verify the VPN is working” a more important habit.