How to clean install macOS Mojave

Now that macOS Mojave 10.14 is available, it is a good time for some users to back up their data and do a clean install for that brand new Mac experience. A clean installation can be a daunting process, since it involves carefully backing up data, removing any useless files, resetting the system and installing the new operating system. However, by following this step-by-step guide, the process should be seamless and straight forward.

Clean install macOS Mojave

Back up your Mac

There are multiple ways of backing up your Mac, but the best method is through the feature built into macOS, Time Machine.

  • Use Time Machine Backup by connecting an external drive to your Mac. Go to System Preferences > Time Machine to setup the disk for backup.

Depending on the amount of data on your Mac, it might take many hours for the backup to complete. So plan this step carefully. It might be wise to leave the backup running overnight.

Download macOS Mojave

Mojave 10.14 can be downloaded from the Mac App Store. It’s more than 6GB in size so the download might take some time.

  • Open Mac App Store and search for macOS MojavemacOS Mojave Mac App Store
  • Download it and when the download completes, the installer will open up. Close it, as we will be using the installation file to create a bootable drive

Alternatively, you can follow our guide to download the full installer for macOS Mojave, without using the Mac App Store.

Create bootable USB Drive

Make sure you have a USB drive handy, with at least 8GB storage capacity. As per our guide, a bootable USB drive for macOS Mojave can be created using either Terminal or via third party apps like DiskMaker X and Disk Creator. We recommended that you use third-party apps, as they don’t require messing around with the Terminal.

Follow the steps in our guide, and come back again to move to the next step.

Format Mac

To format a Mac, we need to reboot into macOS Recovery. It is a set of utilities that allow access to Disk Utility, Time Machine Backup, Online Help and macOS installation.

  • Reboot your Mac
  • Press and hold Command key (⌘) + R right after it turns on, until you see the Apple logo

However, if somehow you are unable to access Recovery, try accessing Internet Recovery instead:

  • Reboot your Mac
  • Press and hold the following keys during right after it turns on: Option (⌥) + Command key (⌘) + R, until you see a spinning globe

Once you are booted into Recovery, we will erase the drive:

  • Click on Disk UtilitymacOS Recvery Disk Utility
  • Disk Utility will look similar to the one in macOS. Select your hard drive and click on the Erase button.macOS Disk Utility
  • In the option that shows up for volume format, select APFS. Enter a name for your disk volume (Macintosh HD is the default name) and click Erase.

Your hard drive will be erased and all data will be removed from it.

Reboot from USB installer

Now that we have the bootable disk ready, plug it into your Mac. You might need a dongle, if you have a MacBook with just USB-C ports.

  • Reboot your Mac
  • Press and hold the Option (⌥) key as soon as the Mac starts, until you see the Startup Manager
  • Select your USB drive and press return

Install macOS Mojave

Once the installer starts, follow the steps to install it on your Mac. It is already formatted and the new volume created, so select it during installation.

After installation is complete, you will be greeted with the setup screen. This means you have successfully installed Mojave on your Mac. You can now restore data from Time Machine and continue enjoying the new features, specially the dark mode.

Read more: