Detecting Hidden SSIDs With Your Favorite Mac OS WiFi Scanner
Detecting hidden SSIDs on Mac OS using your favorite WiFi Scanner form the Mac App Store requires a two step process.
1) Launch your favorite WiFi Scanner for Mac OS app.
2) Open “WiFi Diagnostics” by clicking Option+Airport icon in menu bar. Then click CMD+4 to open Scan feature. Click Scan. If you are near any hidden networks the window should show hidden networks without displaying the SSID name.
3) Now toggle back to your favorite WiFi Scanner for Mac OS app and you should see hidden SSID BSSID in your app.
You will need to click scan continuously to get updated info in your app. Not an ideal solution but at least now hidden networks can be visualized with other networks in your Mac OS WiFi Scanner. This method to show hidden WiFi SSIDs was tested on a MacBook Air running Yosemite (10.10.5)