Your power button will be blank and is the only key that doesn't have any markings on it. In this case, your power button is located on the top right corner of your keyboard above the Delete key. The newer MacBook Air models also have a power button that has been combined with Touch ID.

Instead, it will be the black, unmarked key located in the top right corner of your keyboard above the Delete key. If this is the case, your power button won't have the power icon on it. Newer MacBook Pro models have power buttons that have been combined with Touch ID (that you hold your finger on instead of manually entering passwords). Below, we'll cover how to locate the power button on your specific Mac model. For MacBooks, it is often in the top right corner of the keyboard, and for desktop iMacs, on the back of the computer. The location of the power button can vary depending on the model of your Mac. Option-Shift-Command-Q, this option will immediately take you to the lock screen without confirming as this option will bypass the countdown timer.Press the Power Button to Turn Your MacBook On.If you do nothing, you will be logged out automatically. A countdown will appear saying “are you sure you want to quit all applications and log out now?”. Shift-Command-Q, this option will ask you to confirm.If you have open documents with unsaved changes, you will be asked if you want to save them. You can use this to switch between accounts. This shortcut offers a quick way to log out and leave your Mac. This shortcut will immediately lock the screen. You will need to enter your password when you want to resume working. You may want to do this if you leave your computer unattended. Control–Shift–Media Eject, if your Mac has Touch ID.Control–Shift–Power button, if your Mac does not have Touch ID.The computer will stay on but not the display. You can also put your computer monitor(s) to sleep without putting your Mac to sleep. Option–Command–Media Eject, if your Mac has Touch ID.Option–Command–Power button, if your Mac does not have Touch ID.This way, your Mac will use less power and start up faster. You can put your computer to sleep when you are not using your Mac. Control–Option–Command–Media Eject, if your Mac has Touch ID.Control–Option–Command–Power button, if your Mac does not have Touch ID.You will be asked to save changes if you have documents with unsaved changes. You will be asked whether you want to save unsaved changes if any. Control–Command–Power button, if your Mac does not have Touch ID.This means that you may lose unsaved changes. No dialog box will appear asking you whether you want to save any open and unsaved documents. You can use this shortcut when your Mac is unresponsive.

Mac shortcut to shutdown