In this article we're going to show y'all how to perform a clean install of macOS. There are a number of reasons why yous might want to practice a clean install:

  • You might desire to reinstall the operating system in order to right issues with your Mac - doing a clean install may be a proficient selection if your Mac is running slow or otherwise misbehaving.
  • Doing a clean install allows you to articulate away sometime files that you lot might accept been accumulating for years before installing the operating system onto a freshly formatted disk.
  • A clean install is likewise something you should exercise before selling your Mac or passing information technology on. It allows you lot to remove all your data from your Mac and return information technology to factory settings for next person.
  • A clean install is also something many computer users resort to when they are trying to get rid of a virus (although there is a lot of debate nearly whether at that place are viruses on the Mac).

Whatsoever your reason, a clean install of macOS might solve a lot of problems.

However, things have changed in recent years that mean that a clean install may not exist necessary, then nosotros will start past explaining why you might not need to practice a clean install on your Mac.

You should besides keep in mind that there are multiple ways to practice a clean installation of macOS. The traditional way was to make a bootable copy of the macOS installer on a USB stick and and then reformat your drive earlier installing the bootable copy on to your Mac. There is likewise an even simpler method that allows you lot to use macOS Recovery to reinstall the Mac operating system over the spider web (we have a dissever tutorial well-nigh doing a clean install of macOS using Recovery). Plus, if you are running macOS Monterey on a M1 Mac or an Intel Mac with a T2 chip then there is a new setting in System Preferences that makes wiping your Mac easier than ever. We'll run through all of these methods below.

Should I practice a make clean install on my Mac?

In the past it was helpful to reinstall the system if you wanted to correct some Mac problems, but today this solution doesn't make as much sense.

Since macOS Large Sur, macOS has its home on its own book, which is both read-only and cryptographically signed and sealed (referred to as a Sealed System Volume). This seal is stored either in the T2 chip of the newer Intel Macs or in the Secure Enclave of the Apple M1.

Each component of the system is signed in hierarchical guild, and whatever alter to a component would too invalidate the seal that represents the top level. For further security, these Macs besides practise not start directly from the system volume, but from a snapshot of the system. And snapshots cannot be changed, even by the organization itself.

And so macOS itself cannot be changed by whatever software that yous install every bit a user. Should a trouble occur with macOS during a restart, possibly because a storage space on the SSD is lacking and thus a system component is no longer intact, this volition be recognised past the startup process since the seal will now exist invalid. Should this happen y'all will have to reinstall the organisation.

Still, if your Mac boots upwards without issue and so information technology indicates that there are no problems with the arrangement. Every bit long equally your Mac works (which tin be determined on the ground of the seal), the Mac is considered to be in working social club as it complies with Apple'due south specifications.

For that reason, fifty-fifty if you do run across bug on Macs with T2 scrap or Apple Silicon while running macOS Big Sur or macOS Monterey, information technology makes no sense to reinstall the arrangement yourself.

For those who desire to practice a make clean install and then that no leftovers that belong to an erstwhile system are carried forth, this no longer applies considering none of this information is carried over. All components are checked afterwards installation, then signed and finally the entire organisation sealed again. Again, the seal guarantees that everything is fine and that nada untoward has crept in.

Yet, there is one component of the organization software that is not installed on the read-just system book. All other user-installed programs reside on the book with the user data, including Safari. This means Apple can offer a separate update for the browser and WebKit, so that y'all exercise non have to reinstall the whole system each time.

In the case of Safari and other apps there tin be benefits in cleaning upward your Library folder since it may nevertheless contain remnants of old applications you no longer use.

If you lot feel that you have a lot of this sort of grime on your Mac and then cleaning your drive could be useful, just be prepared that it can be a risky business and y'all may end up deleting something important. Beware that a clean install tin cause more bug that information technology fixes.

You might adopt to apply an application similar CleanMyMac X from MacPaw (£34.95/$39.95 a year, complimentary trial), or 1 of these alternatives: Best Mac Cleaner App.

If you are happy to have the hazard and nevertheless want to wipe your Mac and reinstall macOS - which y'all should definitely practise if y'all are selling or passing on your Mac - read on!

How to wipe your Mac and reinstall macOS

Equally we explained above, there is more than one way to wipe your Mac and reinstall macOS:

  • Make a re-create of the macOS installer on a USB stick, reformat your drive and then install the macOS on to your Mac from the installer.
  • Utilise macOS Recovery to reinstall macOS the spider web.
  • Use the new Erase All Content and Settings option setting in Organization Preferences (bachelor if you are running macOS Monterey on a M1 Mac or an Intel Mac with a T2 chip).

Not only are there three different methods (which nosotros'll run through below) the methods depend on the version of macOS that you lot are running.

There is also the even trickier business organization of installing a clean copy of an older version of macOS on your Mac (Big Sur, Catalina, Loftier Sierra, Sierra, El Capitan, Mojave, Yosemite or an even old version of OS X). Speaking of which, if an old version is what you're looking for, information technology may be worth taking a look at another article where we focus on that entirely: How to download and install sometime versions of OS X on a Mac.

Before y'all begin...

Nosotros recommend that you make a back upward, just in instance something goes wrong. Total instructions here: How to back up a Mac.

Notation that with regard to backups, you lot probably won't want to recover a Time Car backup if you don't want to copy over all the setting and preferences associated with your old organization. You could alternatively sync all your Documents and Desktop with iCloud rather than run a full backup, just brand sure that everything you lot need is in the deject and exist enlightened that you may lose system setting and applications.

Ready? Allow'southward get started.

How to clean install macOS Monterey

How to clean install macOS Monterey

Before the arrival of Monterey it was necessary to create a bootable USB bulldoze or use Recovery Manner to wipe your disk. All the same, with Monterey Apple has made information technology like shooting fish in a barrel to get a factory-fresh installation.

There is a new Erase All Content and Settings pick in the System Preferences menu of Monterey that will allow you lot to reset your Mac to manufacturing plant settings without having to work through the many steps to wipe and format your drives.

Also every bit macOS Monterey, you need to accept a M1 Mac, or an Intel Mac with a T2 scrap inside.

These Intel Macs have the T2 security scrap:

  • MacBook Air from 2022
  • MacBook Pro from 2022
  • Mac mini from 2022
  • iMac 27-inch from 2022
  • iMac Pro
  • Mac Pro from 2022

If you lot have the Erase All Content and Settings option in Monterey then you lot can easily wipe your system, remove all your information and user-installed applications and starting time from scratch. Here's what you need to practise:

  1. Open Organization Preferences.
  2. Click on Arrangement Preferences in the carte bar at the pinnacle of your screen.
  3. Click on Erase All Content and Settings.
  4. Enter your password.
  5. (Yous'll be reminded to do a backup with Time Machine before you brainstorm deletion - just yous tin skip that pace.)
  6. A window will testify you lot what will exist deleted, including Apple ID, Touch ID, accessories, and Find My settings.
  7. Finally yous will demand to log out of your Mac and all related services using your Apple ID.
  8. Earlier your Mac is erased you receive a last alarm, so if you take second thoughts at least you can stop at this point! Erase Mac Monterey
  9. Having clicked the 2nd Erase All Content & Settings your Mac will restart. Eventually you volition see a black screen while it restarts.
  10. One time your Mac restarts yous tin can go through the steps to set it upwardly as new, or you can leave it at this stage for the next owner to prepare upwards. Just turn the Mac off first.

How to do a clean install via Recovery

How to do a clean install via Recovery

We explicate how to reinstall macOS via Recovery hither: How to reinstall macOS, but nosotros will summarise the steps hither.

How you enter recovery fashion depends on the Mac you own.

If you want to enter recovery mode on an M1 Mac y'all demand to press and concur the power button when you lot start upward your Mac and keep to press and concur the push until you see a startup options window appear with an Options icon. Select Options and click Go along.

To enter Recovery on an Intel Mac press Control+R.

  1. Once Recovery starts up you'll run across a macOS Utilities window with options to Restore From Time Auto Backup, Reinstall macOS [version], Safari (or Get Help Online in older versions) and Disk Utility. If you want to wipe the Mac before reinstalling cull Disk Utility.
  2. Run through the steps to erase your Mac as detailed in the How to reinstall macOS guide.
  3. After you accept erased your drive click on Disk Utility > Quit Disk Utility. Or merely Control + Q.
  4. At present choose Reinstall macOS from the options.
  5. Wait while macOS is reinstalled. Look this to take a while.

How to clean install macOS using a bootable USB

How to clean install macOS using a bootable USB

At present for the method that involves using a bootable USB with the macOS installation on it. This might exist the best method if yous already take the installation files downloaded and don't desire to expect for hours for Recovery to download the files.

Before you begin you'll need the following:

  • A 15GB or larger removable USB flash drive to hold the installer file for our chosen version of macOS. (We're going to erase it, so make sure it doesn't incorporate whatsoever valuable data.)
  • Admin privileges for the Mac.
  • A back up, just in case something goes wrong.

Pace ane: Format the external drive

Step 1: Format the external drive

Nosotros're going to re-download the installer file for our called version of macOS and shop it on a USB stick or external drive. Only before you do that you can set the USB drive by reformatting information technology.

Here's how to format your USB drive correctly:

  1. Plug in the USB bulldoze.
  2. Go to Applications > Utilities.
  3. Open up Disk Utility.
  4. Select the bulldoze and click Erase. (The name of the disk needs to be "Untitled", if the Terminal commands below are to work, so rename it if necessary.)
  5. Select Mac Os Extended (Journaled) every bit the format blazon.
  6. Choose GUID Segmentation Map from the Scheme options (if you don't encounter this you are in the wrong view - yous need to select the external drive, not the container below it).
  7. Click Erase.
  8. Disk Utility volition create the partition and set up the drive (it can take a while).
  9. Click Washed.

Step 2a: Get the macOS install file

Step 2a: Get the macOS install file

If you're reinstalling the latest version of macOS, or installing a new version of macOS, the side by side step is relatively like shooting fish in a barrel although the process for obtaining the installer will be unlike.

If you are currently running Big Sur and want to do a clean install of macOS Monterey (once it arrives) then you can download the installation bundle via Arrangement Preferences.

  1. Open System Preferences.
  2. Choose Software Update.
  3. Download the Monterey install files.

If, on the other hand, you want to reinstall Big Sur and are already running Big Sur the best fashion to access the installer for Large Sur is via the Mac App Store. Here's a link to Big Sur on the Mac App Shop. If it'due south Catalina yous want you can get that here. Alternatively open Mac App Store and search for the version you lot desire.

In one case you accept located the version of macOS you want on the Mac App Store follow these instructions:

  1. Striking Download or Get (depending on the version of the Mac App Store you are using).
  2. Yous may go a alert bulletin at this point, telling you that this version of macOS 'is already installed on this computer. Would you similar to continue?' Click Continue.
  3. Enter your Apple ID and countersign.
  4. The Catalina install files volition start to download.

The installer file will exist multiple GB. Big Sur is 12.6GB, for example, so expect downloading to take a while.

The side by side step is worth highlighting for what y'all shouldn't do, rather than what you lot should do:

  1. When the macOS installer has finished downloading the installer will launch automatically, but we don't want to utilise it yet so don't click to start the installation!
  2. Press Control + Q to quit out of the installer.
  3. Find the installer file (information technology will exist located in your Applications folder, or you could search for it using Spotlight (control + Space and start typing Monterey, Catalina or Big Sur).

If yous just desire to install Monterey yous tin skip the next step where nosotros'll exist showing how to dig upwards the installer file for an older version of macOS or Mac OS X.

Step 2b: Get the install file for an older version of macOS

Step 2b: Get the install file for an older version of macOS

For older versions of macOS and Mac Os X it's a bit more difficult to go the install file: Apple doesn't offer downloads of outdated OS versions through the normal store front end, and searching for the name won't detect what yous're looking for.

We have a detailed guide to getting older versions of macOS hither, but we will explicate what you demand to do below.

Depending on the version of macOS you are running, the installers for some versions of macOS tin can be constitute in the Purchased department of the App Store.

Log into the Mac App Store with the Apple tree ID you used and click Purchased in the menu bar along the top. Scan downwardly the listing of apps y'all've purchased or download for free (which is in order of when you downloaded them) and find the proper name of your chosen version: El Capitan, Yosemite or whatever. Click download.

Nonetheless, at that place are a few reasons why this may not piece of work for you:

  • If you have already installed Mojave, Catalina or Big Sur on your Mac y'all cannot easily search for onetime versions of macOS from the Mac App Shop.
  • You won't notice the version of macOS your Mac shipped with in the Purchased section of the App Store.
  • And yous won't notice versions of macOS in the purchased section if y'all never installed that version.

Yet, luckily it is yet possible to go hold of some versions of macOS if yous are running a newer version than Sierra.

  • Big Sur is on the Mac App Store here.
  • Catalina is on the Mac App Store here.
  • Yous tin get macOS Mojave via this link.
  • Download High Sierra here.
  • Sierra is here as a direct download.
  • El Capitan can exist downloaded from this link.
  • Yosemite is available hither.

If you click to observe Catalina, Mjave or High Sierra and the page doesn't open in the Mac App Store try a couple of things: Make sure that the Mac App Store is airtight earlier you click the link; Cut and paste the link into Safari.

As in the step higher up, once yous have downloaded the installer don't run it - just close the installer if it opens.

For more communication on getting concord of even older editions of Mac Bone, seeHow to get quondam versions of OS Ten.

Stride 3: Create a bootable USB disk

Step 3: Create a bootable USB disk

Next nosotros need to turn out USB bulldoze into a bootable USB deejay so that nosotros tin can employ information technology to install a new copy of macOS on our Mac after we take reformatted information technology (that step will come later in this tutorial).

Nosotros've got total instructions on How to make a bootable macOS install bulldoze in a different article, but nosotros'll run through the basics here.

We're going to create the bootable drive using Concluding, which you tin can open on your Mac past pressing Command + Space bar and typing Terminal.

Connect the USB bulldoze that you formatted earlier to your Mac. Make sure it's chosen Untitled - rename information technology if necessary (this will assistance you enter the correct text in Concluding in the next steps).

Creating a bootable installer has been pretty easy since the inflow of Mavericks in 2022 thanks to the Terminal command createinstallmedia that arrived in that version. Here'south how to use it (annotation that the proper noun of the version of macOS will depend on which version you lot are installing):

  1. Open the Final application on your Mac (find information technology by searching using Command + Space and typing Terminal)
  2. Now copy and paste the following text into Terminal (This text is for Big Sur - nosotros include the text needed for the other versions of macOS in this article). When y'all cutting and paste the following text into Terminal practice check that it maintains the -- as nosotros have heard of people pasting in the -- and it converting to –)
    sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resource/createinstallmedia --volume /Volumes/MyVolume (where MyVolume is the name of the external bulldoze y'all are using - it could be Untitled)
  3. Press Return.
  4. Enter your password (yous won't run into the password announced).
  5. Press Return again.
  6. Last will warn that it is almost to erase the drive. If yous want to continue press Y and then Render. The process can take a while, y'all'll see "Erasing Disk: 0%… 10%… 20%… 30%…100%…
  7. Next Concluding volition spend a few minutes copying the installer file to your drive. "Copying installer files to disk… Re-create complete" then on volition appear in the Last window. Again, this tin can take a while - it took our Mac ages to go from 0% to x%...
  8. When the bootable drive is prepared y'all volition see the word Done. It can take a while.

Now you have the installer on the external bulldoze you can use that to install copies of macOS on multiple Macs - which could exist helpful if you are admin for a lot of systems.

Notwithstanding, if you are reading this because you want to do wipe your Mac and do a clean install, read on...

Step 4: Wipe your Mac

Step 4: Wipe your Mac

At present we are prepare to install the copy of macOS from the installer bulldoze on our Mac. If yous desire to practise a fresh installation (and completely wipe your Mac) it'due south time to reformat your Mac's start-upwardly drive.

Here'south how to do a fresh installation of macOS if you lot aren't already running Catalina or Big Sur.

  1. Connect your boot drive.
  2. Start up - or restart - your Mac while holding down the Option key (also known equally Alt). This volition accept you to Startup Manager.
  3. Choose to install your chosen version of macOS from the external drive.
  4. Select Disk Utility.
  5. Select your Mac's start upwardly disc, probably chosen Macintosh Hd or Home.
  6. Click on Erase.
  7. Look for your startup disk to be formatted.
  8. Become back to the main Utilities bill of fare and choose Install macOS.
  9. Choose your startup bulldoze as the location to install macOS.

Once installation is complete, you tin can restore apps and settings from your backup, or download them once more manually.

How to erase your drive in Catalina or Big Sur

Note: if you are running macOS Catalina or Big Sur you volition have ii volumes: Macintosh HD and Macintosh Hard disk drive - Data. If yous desire to do a make clean install of Catalina or Large Sur over an existing installation of Catalina you lot will demand to beginning delete the Macintosh HD - Data volume. We embrace how to practise this in more detail here: How to reset and wipe a Mac.

Macintosh Hd - Data in Catalina/Big Sur is where your data is stored separately to the macOS installation.

  1. Either click on the - button or become to the menu and cull Edit > Delete APFS volume.
  2. Y'all will see a message warning you that this will permanently erase your information. Click on Delete. Do not choose Delete Volume Group.
  3. Await while the volume is deleted.

And then you tin can movement onto deleting your Macintosh HD volume as in a higher place.

Step 5: Install macOS

Step 5: Install macOS

Now you tin use your bootable installer to practise a clean install of macOS on your wiped Mac.

The procedure for installing the Os from the bootable installer is slightly different if y'all have an M1 Mac (also known as Apple Silicon) or an Intel processor within your Mac. We'll run through both methods.

In both cases you will need to have your Mac connected to the Net. It besides needs to be compatible with the version of macOS yous are trying to install (you can't install a macOS older than Large Sur on a M1 Mac).

How to install macOS from a bootable installer

If yous have an Intel-powered Mac here's how to install macOS from a bootable installer:

  1. Plug in your bootable installer
  2. Turn off your Mac.
  3. Press and hold Option/Alt while the Mac starts upwards - go on pressing the key until yous run across a screen showing the bootable volume.
  4. Cull the bootable installer volume.
  5. Click Keep.
  6. Select Install macOS from the Utilities window that appears.
  7. Click Go on.
  8. Now follow the onscreen instructions to practice your make clean install.

If you take an M1 Mac hither's how to install macOS from a bootable installer. As we mentioned above, you can't install a macOS older than Big Sur on a M1 Mac.

  1. Plug in your bootable installer
  2. Turn off your Mac.
  3. Press the power push to turn on the Mac - just keep it pressed until you see the startup options window including your bootable volume.
  4. Choose the bootable installer volume.
  5. Click Proceed.
  6. The macOS installer should open - when information technology does follow the onscreen instructions to practise the clean install.