VPN connections drop. Network changes, server reboots, your laptop sleeps. Without a kill switch, the second the tunnel breaks, your traffic flows over your normal connection — exposing your real IP to whatever you were doing. The kill switch is the safety net.

What a kill switch does

It tells your operating system: "only allow internet traffic that goes through the VPN tunnel." The moment the tunnel disconnects, all internet stops. No real IP exposure, no half-protected sessions. Reconnecting the VPN restores normal traffic instantly.

Two kinds: app-level vs system-level

• App-level (per-app): Only kills specified apps when VPN drops. Useful if you want your torrent client to stop but your browser to keep working.
• System-level: Kills all internet. The right default for privacy users.

How to enable it

Every major VPN has it, often labeled "Kill Switch," "Network Lock" (ExpressVPN), "Always-on VPN," or "Internet Kill Switch." Settings → Connection (or Privacy/Security) → toggle it on. Some apps require admin rights since they install firewall rules.

How to test it

1. Connect the VPN. Confirm your IP changed using our IP checker.
2. Start a download, video stream, or speed test.
3. Force-quit the VPN app (Task Manager / Activity Monitor → End Task).
4. The download/stream should stop within a second. If it keeps running, the kill switch is off or broken.

When you should turn it off

Almost never, if you care about privacy. Exception: troubleshooting connection issues — you can't see what's blocked while the kill switch is killing you. Disable it briefly to diagnose, then turn it back on.

Try it now

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