How-To

How to Test Your VPN for Leaks

A VPN can show "connected" and still quietly leak your real IP address through DNS or WebRTC. Here's how to check in about two minutes — and what to do if it's leaking.

By the VPN Insider editorial desk · Two-minute self-test. June 2026.

The whole point of a VPN is that websites see the VPN's address, not yours. But three side channels can betray your real location even while the VPN is on: a DNS leak, a WebRTC leak, or a plain IP leak when the connection drops. The good news: you can test all three yourself, for free, in a couple of minutes. You don't have to trust the provider's marketing — you can verify it.

What can leak, in plain English

DNS leak. Every site you visit starts with a DNS lookup ("what's the address for this domain?"). If those lookups go to your internet provider instead of through the VPN, your ISP — and anyone watching it — sees every site you visit, even with the VPN on.

WebRTC leak. WebRTC is a browser feature for video and voice calls. To connect peers directly, it can reveal your real IP address to a web page even behind a VPN. It's a browser problem, not a network one, which is why a VPN alone doesn't always stop it.

IP leak on drop. If the VPN connection drops for a second and you have no kill switch, your device falls back to your real IP without telling you.

The two-minute test

  1. Note your real IP first. With the VPN off, visit a leak-test site and write down the IP and location it shows — that's your true address.
  2. Connect your VPN to any server, ideally in another country.
  3. Re-run the test. Reload the leak-test page. The IP and country should now be the VPN's, and your real IP from step 1 should appear nowhere on the page — not in the IP field, not in the DNS section, not in the WebRTC box.
  4. Check DNS and WebRTC specifically. A good test tool lists the DNS servers in use (they should belong to the VPN, not your ISP) and a WebRTC section (it should not show your real IP).
  5. Test the kill switch. With the VPN connected, turn your Wi-Fi off and back on, or switch servers, and watch whether your real IP ever flashes up. If it does, enable the kill switch in your VPN's settings.

Free tools to use

These are independent, third-party testers. Note that they can see your IP when you run the test — that's how they work — so run them, read the result, then come back.

IPLeak.net ↗ ipleak.net

IP, DNS, and WebRTC checks all on one page — the fastest all-in-one.

BrowserLeaks ↗ browserleaks.com

Deep per-category tests, including a dedicated WebRTC page.

Cover Your Tracks (EFF) ↗ coveryourtracks.eff.org

From the Electronic Frontier Foundation — focuses on browser fingerprinting, a related privacy exposure a VPN doesn't fix.

If it's leaking — how to fix it

DNS leak: enable your VPN's own DNS / "DNS leak protection" setting (most have it on by default); if it persists, the provider's DNS handling is weak — a reason to switch.

WebRTC leak: disable WebRTC in your browser or add a reputable WebRTC-blocking extension; some VPN browser extensions do this for you.

IP leak on drop: turn on the kill switch, which blocks all traffic if the VPN disconnects. If your VPN doesn't have one, that's a meaningful gap.

Worth knowing: a VPN does not stop browser fingerprinting — the way sites identify you by your browser's unique configuration. If that's a concern, pair your VPN with a privacy-hardened browser; the EFF tool above shows how identifiable you are.

Bottom line

Don't assume "connected" means "protected." Run the two-minute test when you first install a VPN, after any big update, and any time you're relying on it for something that matters. If your real IP shows up anywhere while the VPN is on, fix the setting — or switch to a provider that passes. The whole appeal of this is that you can check for yourself.

Independent · affiliate-funded · rankings not for sale. The testing tools named here are independent third parties we don't profit from. We may earn a commission via some VPN links, but never on our guidance. Informational only.

VPNInsider.org · How-To · updated monthly · June 2026.