The Fastest Way to Lock or Sleep Your Screen in Mac OS X
Locking your Mac’s display (or “sleeping” the display) can be a great security measure when paired with a user account password. While it won’t prevent the outright theft of your Mac, it can be a quick and easy way to prevent nosy family members or coworkers from getting access to your data.
In order for a Mac lock screen command to be effective, you’ll first need to configure System Preferences to require your user account password when unlocking or waking up. To do this, head to System Preferences > Security & Privacy > General. Check the box next to “Require Password” and set an interval that meets your workflow. If you want the highest level of security, set it to “immediately.” If you often find yourself accidentally locking your screen, set it to 5 seconds so that you can quickly unlock the display without having to enter your password.
Next, you’ll need to decide on the exact functionality you want: lock (sleep) the display only, or sleep the entire system. Locking or sleeping the display will shut the display off but keep the Mac running in the background. If you performed the steps above to require a password, users will need to enter the correct account password in order to unlock the display.
Lock or Sleep Only Your Mac’s Screen
To lock your Mac’s screen, simultaneously press the following keys: Control + Shift + Eject. If you have a newer Mac that doesn’t have an optical drive (and thus has no eject key on the keyboard, such as the Retina MacBook Pro), the command is Control + Shift + Power. In both cases, you’ll see your Mac’s display shut off immediately, while the system continues to run in the background.
Related: Once your screen is locked, learn how to set a custom lock screen message.
Performing a lock or display sleep command is useful for situations in which you’ll only be gone for a few minutes, as it allows you to jump immediately back to work. It’s also a good idea to use if you want to lock your Mac but have applications running in the background, such as a rendering operation or an encryption sequence. The Mac will still chug away at its task; the only difference is that anyone without the password won’t be able to access it.
Sleep Your Entire Mac
The second option is to sleep the Mac entirely. MacBook owners are familiar with sleep; it occurs every time they shut their computer’s lid, or automatically after a user-defined period of time. But users can also trigger an immediate sleep state with a simple keyboard command: Command + Option + Eject. Optical drive-less Mac owners can repeat the substitution discussed above and replace the Eject key with the Power key, resulting in a command for Retina MacBook Pro owners, et al. of Command + Option + Power.
Your Mac will immediately go to sleep, shutting down all functions and requiring a password to resume. Users running on battery power who need to step away from their Macs may prefer this option over a locked screen. The practical effect is the same (preventing others from accessing your Mac), but this latter option saves battery power while the user is away. On the other hand, this will stop all background tasks, discussed above, and may not be ideal for users who want their Macs to keep working while they grab a coffee or stop for a bathroom break. Also, it takes longer to wake up from a sleep state than from a display lock state, although on modern Macs with fast SSD storage the time difference between the two options has shrunk considerably.
It’s recommended that users experiment with both options to find the one that suits them best. It’s also likely that users, especially those “on the go” with MacBooks, will find occasion to use both frequently. Regardless, having a strong user account password and taking a moment to ensure that your Mac is locked while you are away are both crucial steps to protecting your data.