macOS

How to Clean Install macOS 12 Monterey in a Few Simple Steps

The macOS 12 Monterey is the next version of the Mac operating system following the Big Sur, which is reported to be released this fall. However, if you already want to try it out, the public BETA version is now available. And if you are ready to update your macOS, we recommend that you do a clean install on Mac.

The new software is packed with many upgrades like universal control, new Facetime capabilities, SharePlay, privacy updates, a new Focus feature, Notes upgrades, and many more. But there are several things to consider before you upgrade your macOS. Is it compatible with your device? And do you have enough space for the new macOS installation?

In this article, we’ll talk about what a clean install is and how you can do one for macOS Monterey to your Mac.

What is a Clean Install and Why We Recommend It?

Mac clean install simply means installing the OS on a newly formatted or erased drive. The common way of installing a new OS is to install it on top of the current macOS. However, this can lead to residual files from the old OS that are no longer being used.

When you do a clean install, it’s like having a fresh and clean start with your Mac. All unnecessary system files and unused applications are deleted, speeding up your computer as if it was brand new. Unfortunately, all the apps and files you use are also erased, so properly backing up your files is crucial.

Is macOS Monterey compatible with your Mac?

macos monterey beta

First off, not all Macs are compatible with the new macOS Monterey. If your Mac is one of the older generations, you might not be able to update to Monterey at all. It’s also worth noting that a few of the new features will only be available on Macs with M1 processors. And even if you do have an M1 Mac, some features are exclusive to the 16GB variant.

Here’s a list of Macs compatible with Monterey:

  • MacBook Air‌ – 2015 and later
  • MacBook Pro – 2015 and later
  • MacBook – 2016 and later
  • Mac mini – Late 2014 and later
  • ‌iMac‌ – Late 2015 and later
  • ‌iMac‌ Pro – 2017 and later
  • Mac Pro – Late 2013 and later

On the contrary, here are the other Macs that can’t run Monterey:

  • MacBook – 2015
  • iMac – 2014 and early 2015
  • MacBook Air – 2013 and 2014
  • MacBook Pro – 2013 and 2014

If your Mac is compatible with the new macOS update, then buckle up! This entire process will take 30 minutes to more than an hour depending on your Mac and internet speed.

6 Steps to Clean Install macOS 12 Monterey

Step 1: Clean Up Your System

As we prepare to clean install macOS Monterey, we recommend that you clean up your system first. This will make the backup lighter, which in return will help you save time. You will also be able to free up more space and get rid of unnecessary data stored in your Mac.

CleanMyMac X is an app that can help you clean up your drive. It is authorized by Apple and can clear up to 10GB worth of junk.

Here are the steps on how to clean up your system using CleanMyMac X:

  1. Download the CleanMyMacX app here. This app is available to download for free.
  2. Once the installation is done, open CleanMyMacX on your Mac.install clean my mac
  3. Select the Smart Scan on the upper left of the screen, and click the Scan button. Wait for the scan to finish.start smart scan
  4. The results will show up, and you can review the files that you want to be deleted. Click Remove to clear them from your system.remove files with cleanmymac

Now we’re all set for the next step, which is backing up your Mac.

Step 2: Backup Your Mac

This method is where you will need the external hard drive. It is crucial to backup your data because, as we mentioned earlier, a clean install is like having a fresh and new Mac.

For this step, you can either backup using Apple’s Time Machine or use Disk Drill to backup your Mac. We recommend DiskDrill because it has a byte-to-byte backup feature that allows you to make a complete backup copy of your drive. If ever some files will be lost while doing the clean install of macOS, Disk Drill also has the capacity to restore and recover lost data.

In order to back up your files using Disk Drill, you have to install the app first. To do that, follow the steps below:

  1. Go to www.cleverfiles.com/download.html to download and install the Disk Drill. After downloading, just drag the Disk Drill’s icon to the Applications folder. install disk drill
  2. Once the installation is done, launch the Disk Drill app on your Mac via the Spotlight Search.launch disk drill

Next, we’ll proceed to the steps on how to back up your Mac via Disk Drill.

  1. On the homepage of Disk Drill, select the option Byte-to-Byte backup located on the left sidebar under the Extra Tools.
  2. Disk Drill will show a list of drives available for backup into a disk image. Select the drive, then click the Create Backup button. We recommend that you backup the whole drive so nothing will get lost.backup your system drive with disk drill
  3. Choose a location where you want the DMG file to be saved. You can use your external hard drive here. Just make sure that it has enough storage space for your backup.
  4. Click Save, and your backup will begin. This will take a few minutes, depending on the size of the backup.save your system drive backup
  5. You will see this on the screen once the backup is completed:completed disk backup
  6. Click Done to exit the window. To check if all files have been backed up, go to the homepage of Disk Drill > select Storage and Devices > click the Attach disk image button > select and attach the name of the backup dmg.attach disk image
  7. After that, scan the attached DMG file. When that’s complete, click on Review found items and check through the results to see if all the files were saved.review found items

💡 Note: Disk Drill may not be able to maximize its data recovery if the drive is encrypted by M1 or T2 chips which have added security features. Because of this, it’s best to do your backup via Time Machine.

Step 3: Download macOS Monterey

Now that you’re done cleaning up your system and backing up your Mac, you are all set to download and install the new macOS Monterey.

Since the full version of macOS Monterey is not yet out, only the Public BETA version is available for download. To proceed, follow the steps below:

  1. Launch a browser on your Mac and go to https://beta.apple.com/sp/betaprogram/.
  2. Sign in using your Apple ID.login on apple beta page
  3. Then, click the Enroll Your Devices button, and select the macOS tab.
  4. Next, click the Download the macOS Public Beta Access Utility button and run the installer.Download the macOS Public Beta Access Utility
  5. After that, the Software Update will open. Then finally, click Upgrade Now.upgrade now your mac

⚠️ Important: You have to cancel the installation once it starts. Just save the installer on your Applications folder. This is a crucial step in doing a Mac clean install, as it will lead us to the following method.

Step 4: Create a Bootable Drive via Disk Drill

Now that the installer is saved on your Applications folder, it’s time to create a bootable drive.

But first, you need to prepare your other external hard drive where you will keep the macOS Monterey installer. The external drive should have at least 16GB worth of storage, and it should be formatted.

Below are the steps on how to create a bootable drive via Disk Drill:

  1. Launch the Disk Drill app on your Mac.
  2. Select the macOS installer on the options located on the left panel. Make sure you insert your flash drive. It is best to name this flash drive as “macOS installer drive” so you can easily identify it.
  3. Then, choose the macOS Monterey installer, select the destination of the flash drive.
    ⚠️ Warning: All data on destination will be erased!
  4. Finally, click the Create macOS installer button.create mac os installer
  5. Disk Drill will now create a macOS Installer Boot Drive. Click Done once the process is finished.created mac os installer

Step 5: Update Your Startup Security Settings

To make things clearer, we will divide this section depending on the security chip installed on your Mac.

Update The Startup Security Settings For Old Macs

The set of instructions below are applicable to Macs that do not have a security chip installed. If you are not using this type of Mac, you may skip this part.

  1. Shut down your Mac.
  2. Then, press the Power button and hold Command + R. Hold for five seconds or until the Apple logo shows up on the screen.
  3. Your Mac will be in Recovery Mode. Enter your password to proceed.login into recovery mode
  4. Then, the macOS Utilities window will appear. Click Utilities and select Startup Security Utility located at the top bar menu.
  5. Check if the option “Firmware Password Protection” is in off state. If it is on, turn off password protection.disable firmware password protection

Update The Startup Security Settings for Macs with T2-powered Chips.

If your Mac is T2-powered, this section is for you. Before erasing your current macOS, you have to activate booting the Mac from USB. Do this by updating the startup security settings.

  1. Shut down your Mac.
  2. Then, press the Power button and hold Command + R. Hold for five seconds or until the Apple logo shows up on the screen.
  3. Your Mac will be in Recovery Mode. Enter your password to proceed.
  4. Then, the macOS Utilities window will appear. Click Utilities and select Startup Security Utility. select Startup Security Utility
  5. Press the button Enter macOS password, and enter your password again when the StartUp Security Utility window appears.
  6. Under Secure boot, select Medium security.
  7. Select Allow booting external media under the Allowed boot media. Then, close the window by clicking the red X icon. Settings will now be applied.Select Allow booting external media
  8. Finally, shut down your Mac.

Update The Startup Security Settings For Macs With M1 Chips

For Macs powered by M1 chips, these are the steps that you need to do:

  1. Shut down your Mac.
  2. Turn it back on and don’t let go of the power button. Keep holding the power button until you see the Startup Options window.Startup Options window
  3. Click Options or the gear icon, and then click Continue.load macos recovery on m1 mac
  4. You might be asked for your administrator password at this stage or a couple of steps later. Enter the password to proceed.
  5. Instead of using the utilities in the main window, go to the top menu bar, and select Utilities –> Startup Security Utility.select Startup Security Utility
  6. Select your system drive and press the Security Policy button.press the Security Policy button
  7. On the next window, select Reduced Security option, then click OK button.select Reduced Security option
  8. Close the window and shut down your M1 Mac

Step 6: Erase Your Current macOS and Install macOS Monterey

After we have done all the necessary steps, your clean install of macOS Monterey will now begin. The next step is erasing your current macOS and finally installing macOS Monterey. For clarity, we will also divide this part depending on the type of Mac that you are using.

For older Macs that do not have security chips and for T2-powered Macs

  1. Connect your “Install macOS Monterey Beta” USB drive where you placed the bootable installer.
  2. Start your Mac by holding down the Option key.
  3. The Recovery window will list the boot options. Boot from the Install macOS Monterey Beta.
  4. Then, enter your account password to access macOS recovery menu.
  5. On the menu options, choose Disk Utility. The Disk Utility window will appear.open disk utility in recovery mode
  6. Click the view button and select Show All Devices. From there, select your internal drive with the name Apple HDD\SSD and some numbers.erase your system drive
  7. Then, click Erase. Make sure to keep the format as APFS. Click Erase again.finally erase disk
  8. Your current macOS is now deleted. Close Disk Utility to go back to the Recovery window.
  9. While your “install macOS Monterey Beta” bootable USB drive is still connected to your Mac, click Install macOS Monterey Beta. Then, click Continue.install mac os monterey beta

The installation will begin, and macOS Monterey will do the rest of the process. Your Mac will be restarting a few times and the installation will take around 30 minutes or more.

For Macs with M1 chips installed

  1. Connect your “Install macOS Monterey beta” USB drive where you placed the bootable installer.
  2. Turn your M1 mac on and don’t let go of the power button. Keep holding it until you see the Startup Options window. Select Install macOS Monterey beta and click Continue.Select Install macOS Monterey beta
  3. You will be presented with the macOS Beta installer assistant window. Close it by pressing Install macOS Monterey beta -> Quit Install macOS.Quit Install macOS
  4. In the next pop-up window, press Quit. This step is needed to enter Disk Utility to erase your main system drive.confirm exit from install
  5. Choose Disk Utility in the list of options.Choose Disk Utility in the list of options
  6. Click the View button and select Show all devices. Then select your internal drive – with the name Apple HDD\SSD and some numbers.select Show all devices
  7. Then, click Erase and choose APFS. Click Erase again.Erase and choose APFS
  8. On the next window click “Erase mac…click erase mac
    ⚠️ Warning: this will erase all your content stored on the Mac. Internet connection will be required to reactivate M1 Mac after erasing.
  9. On the next window, click Erase Mac and Restart. This will start the process of erasing the main drive and will automatically restart your Mac for being reactivated after erasing is done.click Erase Mac and Restart
  10. After auto restarting, a window to Activate Mac will appear. Remember, you need to have an internet connection to finish this process. Process of activation is automated and does not require user interaction.activate mac window
  11. When activation is done, click Exit to Recovery Utilities.click Exit to Recovery Utilities
  12. Shut down your Mac.
  13. Then finally, we go back to step 2. Turn on your M1 mac and don’t let go of the power button. Keep holding it until you see the Startup Options window. Select Install macOS Monterey beta and click Continue.
  14. You will be presented with the macOS Beta installer assistant window again. Now select the language you want to use during installation, and click Continue to fire up macOS Monterey beta installation.Install macOS Monterey beta

FAQ

Reinstalling macOS on Recovery mode does not erase your data. However, if your data is corrupted, this will affect the reinstallation process.
Yes, but not too often. Doing a clean install can also help you speed up your device. Just make sure you have proper backups when you do it.

For T2-powered Macs and Macs without a security chip: Shut down your Mac. Then press and hold Command + R to boot your Mac into recovery mode.

For Mac with M1 chip: Shut down your Mac. Turn it back on and hold the power button until you see the startup options window. Then click the gear “Options” icon, and then click Continue.

Conclusion

Doing a clean install of the macOS Monterey may seem like a tedious task but that’s just the way it is. Once you are done with all the processes, you will feel the difference between doing a regular install for a new macOS, compared to doing a clean install.

Have fun exploring your new macOS12 Monterey!

Mako Young is a writer for all things tech. He's been writing about Macs for years and has been using Macs for more than a decade. When he isn't reading about the latest news on Apple, he's busy studying cybersecurity, cryptocurrency, cloud computing, and other IT-related sectors.
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