ipblinker

ipblinker sits in the menu bar and watches the public address your traffic leaves from. If your VPN stops protecting you, it tells you quickly. A breathing glyph shows the state, and notifications stay neutral.

It decides from what the network shows, not from the VPN’s status light, and warns only when two independent checks agree. It runs on macOS 14 or later.

1. Observe. ipblinker checks the public address seen over the default route.
2. Compare. It checks the address seen when bound to the physical interface.
3. Decide. If the two match, nothing is tunnelling, whatever the route table says.
4. Warn. Only then does the state change to exposed.

Captive portals, being offline and probe failures each get their own state, so they do not trigger a false alarm. The menu also has rule toggles, a “learn home” network fingerprint and a Presentation Mode.

A policy engine you can test

All the “never cry wolf” rules live in one pure state-machine reducer, so the alerting policy has unit tests like any other code. Two independent signals must agree before the state becomes exposed. Naked and tunnelled probes use different endpoints, so no third party can link the two identities.

ipblinker is for Mac users who rely on a VPN: remote workers, journalists, travellers and anyone who needs to know the moment their real address is exposed. It warns only when two independent checks agree, so an alert means something.