Choose your operating System
Windows
Open a Elevated Command Prompt, type:
netsh wlan show profile WiFi-name key=clear
and replace Wifi-name with your wifi name. If you do not know your wifi name, you can type:
netsh wlan show profile
Mac
Open Terminal and type:
security find-generic-password -ga Wifi-name | grep “password:”
and replace Wifi-name with your wifi name. You will get a pop-up window requesting your local adminitrator user, type it in and you should get the password