• If your Mac computer is malfunctioning or you’re looking to sell it, it might be time to perform a factory reset on the device.
• A factory reset will wipe all your data and applications off the Mac, restoring it to its original, default state.
• Performing a factory reset on a Mac only takes a few minutes, but it may not work directly the same way on every computer.
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Everyone’s heard the old troubleshooting tip: “Just turn it off and back on again.” It’s a tip that works surprisingly often – but if you’re stuck in a situation where your Mac is bugging out and nothing is fixing it, it might be time to try a more extreme solution: factory resetting.

A factory reset will wipe your Mac computer, restoring its software to the state it was in when it left the factory. That means that all your personal files and data will disappear. This is a good idea if all other troubleshooting has failed for your Mac, you’re trying to wipe out your private data, or if you’re selling or giving away your Mac to someone else.

Here’s how to factory reset your Mac, wiping out all data, including a few tips in case it doesn’t work.

How to factory reset a Mac computer

Before anything, if you don’t want to lose the files you have saved on your computer, you should back them up. You can do this through Time Machine, Apple’s official backup application, which will copy all your files onto an external drive. You can also backup onto iCloud, or manually move the files you want to save onto an external drive.

If you’re giving your computer away, also make sure that you’ve signed out of iTunes, iCloud, and iMessage – there’s a chance your Apple ID data will remain on the drive after you reset it, and you don’t want anyone gaining access to your account.

Once you’re ready:

1. Turn your Mac computer off.

2. Press the power button to turn it on, then immediately press and hold Command (⌘) + R. Keep holding it until you see either the Apple logo, or an animation of a spinning globe.

3. After a few moments, the macOS Utilities window should appear – this is known as Recovery Mode.

4. Select “Disk Utility” and click “Continue.”

5. In the menu bar at the top of the screen, select View > Show All Devices.

6. In Disk Utility’s sidebar, which displays all the currently installed disks and volumes, select the drive you want to erase. Although you can erase whatever you like, in most cases, it’s best to erase the whole disk – the tab highest up in the tree.

7. Click the “Erase” button at the top of the screen, and fill out the fields it opens:

• Fill in a name for the disk. It’s a good idea to just copy the name that already exists, for clarity’s sake.
• Choose the format. Disk Utility will choose a compatible format by default. If you’re erasing your disk before installing macOS High Sierra or later for the first time, will be using the disk with a Mac that isn’t using High Sierra or later, or are going to use the disk as a Time Machine backup, choose “Mac OS Extended (Journaled).”
• If shown, choose the scheme. In almost all cases, you should choose GUID Partition Map.

8. Click “Erase.”

9. It will take a few moments for the disk to erase. Once it’s done, click the Apple logo in the top-left corner of the screen, and click “Quit Disk Utility.”

At this point, if you’re just trying to erase your disk, you’re done. If you want to set things back up, however, you can navigate back to the macOS Utilities menu and select either:

• “Restore From Time Machine Backup,” which will restore your files if you used Time Machine to back them up.
• “Reinstall macOS,” which will install a new copy of macOS onto your system.

What if my computer won’t boot into recovery mode?

There’s a chance that when you start your computer holding down Command (⌘) + R, it will simply boot up normally and proceed right to your login screen, or just a blank screen. If this is the case, there’s a chance that you may not have a Recovery Partition – the part of your disk that allows you to factory reset. Here’s how to check if you have one:

1. Open Terminal by searching for it in Spotlight or Finder.
2. Type “diskutil list” and press Return.
3. Terminal will show you all the volumes and partitions on your disk. The first section (called “/dev/disk0”) should have a partition called “Apple_Boot Recovery HD.”

If it doesn’t have that partition, chances are that you don’t have a Recovery Partition.

At this point, there’s a few different steps you can take. You can try resetting your Mac through Internet Recovery – press and hold Command (⌘) + Option + R – which will connect to the internet to create a Recovery Partition and activate Recovery Mode. Not having a Recovery Partition isn’t a good sign for your system, so it’s worth trying to reinstall your macOS, even if you weren’t originally planning on it.

If this doesn’t work either, you should contact Apple directly, or consider using third-party applications designed to create Recovery Partitions.

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