Fixing Mac Device Wi-Fi password issues as stated here:-
Step 1: Type Key chain Access into Spotlight search (Screen Shot 2014-05-16 at 2.54.07 PM) at the top-right menu bar.
Step 2: In the sidebar, make sure you click on Passwords, then search for the network you want the password for and double click on it.
Step 3: Now click on Show Password. Confirm your administrator username and password.
Step 4: You may be prompted to enter your administrator name and password again.
Step 5: The Wi-Fi password should appear in the text box next to Show Password.
Key chain Access also stores your applications, internet and web form passwords, so you’re in luck if you forget one of those too. If password management is something you are not great at, consider looking into 1Password on the Mac App Store. It’s a useful app for keeping track of passwords wherever you use them, especially in light of recent events like the Heart bleed bug.
If you know of any other password tricks for mac OS, let us know in the comments section down below. You can also read all of our recent password-related articles for not just the Mac, but iOS devices and beyond. Moreover, if you are looking for other tutorials like this one, be sure to check out our quick tips section for other how tos and helpful articles. We hope that our end users get instant answers for to know Wi-Fi passwords on Mac apple systems.
Another Alternative Methods as described:-
Chances are that you never think of your wi-fi password after your set it up. So how can you recover a saved password from your Mac when you forget it? All you need is your administrator account password.
Open Keychain Access app. It is located in the Applications > Utilities folder.
1. Select the System key chain in the left menu bar, and select Passwords from the category menu. This will filter the key chains to just your stored passwords.
2. Double click on the name of the network for which you want to view the password.
3. This will open a new window specific to that stored password. Then Click on the ‘Show password’ checkbox.
4. You will be asked to authenticate with a username and password. This account must have administrator privileges on your Mac.
5. If you are unsure what your username is, open up the Finder app and look for the home icon in the Favourites sidebar. Your home folder will called the same as your username.
6. After successfully authenticating, the Wi-Fi network password will be revealed in the previous window as shown into your Mac book device.
How to Know My WiFi Password on MAC?