How to Reinstall macOS on Your MacBook Air/Pro or iMac: 3 Best Ways

Written by

Ojash

Reviewed by

Hashir Ibrahim

Last updated: July 27, 2024

Expert verified

When your Mac starts slowing down, crashing, or showing that dreaded spinning wheel too often, it’s time for a fresh start. Sure, you can try clearing out memory and deleting cache, but sometimes these fixes just don’t cut it and you have to reinstall macOS. I know, it sounds a bit technical, but I’ve been through this with my MacBook Air and iMac. I’ve found the three easiest ways to reinstall macOS and I’m going to show you how.

How to Prepare for the macOS Reinstallation

Before you begin the macOS reinstallation process, you need to do the following:

1. 💾 Backup Your Data: Reinstalling macOS will erase all the data on your Mac’s startup disk. So, back up your Mac data before proceeding using Time Machine or any other backup method.
2. 🔍 Check Compatibility: Your Mac must be compatible with the latest macOS version. You can check this on the Apple website under the system requirements section.
3. 🌐 Check Your Internet Connection: You’ll need a stable internet connection to download and reinstall macOS. Make sure your Wi-Fi or Ethernet connection is working correctly.
4. 📊 Check Your Disk Space: Before reinstallation, ensure you have enough disk space for the new operating system. You can check your available disk space by going to the Apple menu > About This Mac > Storage.
5. 📥 Download the Latest Version of macOS: Download the latest macOS version from the Mac App Store. Doing this before you start the reinstallation process saves time.

3 Ways to Reinstall macOS on Your MacBook Air/Pro/iMac

Now that you have prepared your Mac for installation of macOS, I’ll share 3 methods to reinstall macOS.

1. Using a Bootable USB Drive

From personal experience, I’ve found that using a bootable flash drive to reinstall macOS on your MacBook Air, Pro, or iMac is the easiest. It’s a bit old school but more straightforward than you might think.

Here are the steps to follow:

a. Create a Bootable macOS USB Drive

1. Download the macOS installer from Apple’s official website. The installer will be downloaded to the Downloads folder on your Mac.

2. Insert a flash drive with at least 16GB of storage.
3. To create a bootable USB on Mac, open Disk Utility, select the USB drive in the left sidebar, and click Erase in the top menu.

4. Type a name for your USB, choose Mac OS Extended (Journaled) as the format, and click Erase to format the USB.

5. Open Terminal from the Utilities folder and type the following command:

sudo /Applications/Install\ macOS\ Sonoma.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Please note that this particular command is for macOS Sonoma. If you downloaded a different macOS version, replace Sonoma with the appropriate name.

sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install/ macOS/ Sierra.app

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

sudo /Applications/Install OS X Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install OS X Yosemite.app

6. Enter your admin password when prompted, and press Enter.
7. Now, wait for the process to complete.

b. Reinstall macOS

1. Shut down your MacBook.

2. Insert the bootable macOS USB drive into your Mac.
3. Turn on your Mac and press the Option ⌥ key on your keyboard.

4. Select Install macOS 13 beta from the Startup options and press the Enter key to boot.

5. Select your preferred language from the list and press the right arrow icon in the bottom right corner.

6. Select Disk Utility from the list and click Continue.

7. Click the View icon in the top left corner and select Show All Devices from the drop-down menu.

8. Now, choose your main drive in the left sidebar and click the Erase button at the top.

9. A pop-up window will appear. Here, type your drive’s name (Macintosh HD), choose its format (APFS) and scheme (GUID Partition Map), and click Erase.

10. Wait for the drive to erase and click Done. Then, close the Disk Utility window.

11. Go back to the macOS Recovery menu, click Install macOS 13 beta, and press Continue.

12. Click Continue again to start the installation process.

13. Click Agree on the software license agreement.

14. Next, select the drive you want to install the macOS to and click Continue.

15. Wait for the installation to complete until you see the macOS hello screen.
16. Your macOS has been successfully installed. Now, you can set it up according to your preferences.

2. Using the Recovery Mode

Next up, let’s talk about using Recovery Mode to reinstall macOS on your MacBook Air, Pro, or iMac. This method is a lifesaver if you don’t have a bootable flash drive handy. I’ve used Recovery Mode several times, and it’s surprisingly quick.

Here are the steps to reinstall macOS by booting your Mac into Recovery Mode:

1. First, make sure your MacBook Air/Pro/iMac is connected to the Internet.
2. Turn off your Mac and turn it back on while holding down the Command ⌘ + R keys on your keyboard. Keep holding the keys until the Apple logo appears.

3. This will boot your Mac into the Recovery Mode. Once it loads, select Reinstall macOS and click Continue.

4. Follow the on-screen instructions to select your startup disk and begin the reinstallation process.

5. After the installation is complete, your Mac will restart and display the Setup Assistant. Follow the on-screen instructions to set up your Mac, including selecting your language, creating a user account, and configuring settings.
6. Once you’ve completed the setup process, you should have a fresh macOS installation.

3. Using Mac Internet Recovery Mode

Internet Recovery Mode is a powerful solution for reinstalling macOS, especially when your Mac’s recovery partition isn’t available or you’re dealing with a more complex issue.

As someone who has relied on Internet Recovery in a pinch, I can vouch for its effectiveness. This method is a bit different as it uses your internet connection to reinstall macOS directly from Apple’s servers.

Here’s how to start your Mac in Internet Recovery Mode to reinstall macOS:

For Intel-Based Macs

1. Turn off your Mac by pressing and holding the Power button until it shuts down completely.
2. Press the power button to turn on your Mac. Immediately press and hold the Command ⌘ + Option ⌥ + R keys until you see a globe image.

3. Next, tap Choose Network and select a stable Wi-Fi network from the drop-down menu.

4. Enter the Wi-Fi password.
5. After establishing a stable internet connection, your Mac will begin downloading the necessary installation files. This can take anywhere from a few minutes to more than an hour, depending on the speed of your Mac and internet connection.
6. Once the download is complete, you’ll be directed to the macOS Utilities window, where you can initiate the installation process.

For M1 Macs

On Apple Silicon Macs, standard macOS Recovery has been integrated with M1/M2 Mac Internet Recovery Mode. This means there is no difference between booting an M1 or M2 MacBook Pro to macOS Internet Recovery and entering a normal macOS Recovery.

What If Recovery Mode Is Not Working

When you’re unable to access Mac’s Recovery Mode due to a non-functioning Command ⌘ + R or a damaged recovery partition, there are alternative methods to reinstall macOS. Here’s a quick overview:

1. 🌐 Internet Recovery Mode: This is an online version of the standard Recovery Mode. If your Mac can’t boot into the regular Recovery Mode, it will automatically switch to Internet Recovery Mode. This lets you access macOS Utilities.
2. 🔄 Fallback RecoveryOS Mode: Exclusive to Apple silicon Macs, this mode is a backup recovery system. To enter Fallback RecoveryOS, simply hold the Power button from a shutdown state on your M1 Mac.
3. 🔧 DFU Mode: Different from the other startup options, DFU (Device Firmware Update) mode is embedded into the hardware’s SecureROM. It’s typically used to restore a malfunctioning device to proper working condition, often in conjunction with Apple Configurator 2.
4. 💾 Create a USB Installer: First, download the macOS installer (like Big Sur, Ventura, or Sonoma) from the Mac App Store or online. Install it on a bootable USB drive. Then, connect this USB to your Mac and boot from it to reinstall macOS.

Post-Installation Steps for macOS

After you’ve reinstalled macOS, you must take a few post-installation steps to make sure everything runs according to your preference. Here are the essential post-installation steps for macOS:

1. 💾 Restore Your Data from Backup: You can use Time Machine or any other backup method to restore your data to your Mac.
2. 📥 Install Essential Software: Install the essential software that you use regularly, such as web browsers, productivity apps, media players, and other tools.
3. ⚙️ Configure Your Mac’s Settings: Take some time to configure your Mac’s settings. You can adjust settings for your desktop background, screensaver, dock, mouse, trackpad, and more.
4. 📧 Set Up Your Email and Other Accounts: If you use email and other online services, set them up on your Mac. This can include setting up your email accounts, iCloud, Dropbox, and other services.
5. 🔒 Set Up Security Features: Make sure to set up any security features you need, such as a password or Touch ID, to keep your system and data safe. Also, consider installing an antivirus to protect your data.

When to Reinstall macOS?

Over time, your Mac can become cluttered with files and applications that can slow it down or cause other performance issues. Reinstalling macOS can clean up your Mac and restore it to its original state.

Here are some common reasons why you might want to reinstall macOS:

• 🐢Your Mac is running slow or is unresponsive
• 💥Your Mac frequently crashes or freezes
• 🦠 You’ve encountered a virus or malware on your Mac
• 💰You want to sell or give away your Mac and want to erase all personal data

Do You Really Need to Reinstall macOS?

Although reinstalling macOS can clean up your system and improve its performance, you can use third-party software like MacKeeper to keep your Mac running smoothly without reinstalling macOS.

Reinstalling the system software is a hectic process, and you risk losing your data if something goes wrong. To avoid such an unfortunate situation, try MacKeeper’s many features to keep your Mac in the best shape.

Some top features of MacKeeper include the following:

• Memory Cleaner: This feature optimizes your Mac’s memory usage by freeing up RAM being used unnecessarily. This can improve your Mac’s performance by reducing the time it takes to load apps and files.

Here’s how to use MacKeeper’s Memory Cleaner:

1. Download and install MacKeeper on your Mac.
2. Select Memory Cleaner in the left sidebar under Performance.

3. Click Open.

4. Tap Clean Memory, and MacKeeper will free up available memory.

• Safe Cleanup: This feature helps clear disk space by identifying and removing unnecessary files and leftovers from your Mac. This can speed up your Mac by freeing up space while preventing clutter and data loss.
• Login Items: This feature allows you to manage the apps that launch automatically when you start up your Mac. By controlling which apps launch at startup, you can speed up your Mac’s boot time and reduce the memory and CPU usage required.
• Duplicates Finder: It finds and removes duplicate files on your Mac. Duplicate files can take up valuable disk space and slow down your Mac’s performance, so removing them can improve your Mac’s speed and free up space.
• Antivirus: MacKeeper includes an antivirus program to protect your Mac from malware, spyware, and other threats. The antivirus software can check your Mac for malware, remove infections, and provide real-time protection against new threats.

Troubleshooting 6 Common Issues While Reinstalling macOS

macOS reinstallation is a process that takes work and things don’t always go right. Here are some tips that might come in handy if you run into any issues while reinstalling macOS:

1. Compatibility Issues 

Compatibility can be a headache when reinstalling macOS, especially when working with older hardware or software. Before diving into the installation process, double-check the system requirements for the macOS version you want to install.

 Make sure your Mac meets the minimum requirements for that specific version. You can easily find out what your system can handle by going to About This Mac in the Apple menu.

2. Slow or Stuck Installation 

If your installation is stuck, try restarting your Mac by holding the Power button to shut down, then press it again to restart. If this doesn’t work, booting your Mac into Safe Mode, which runs it with minimal necessary components, might help get things moving.

3. No Internet Connection 

If you’re having trouble connecting to the internet during installation, ensure your Wi-Fi or Ethernet is active and connected. If issues persist, try a different network, move closer to your router, or switch Wi-Fi networks.

Still stuck? Reset your router or modem, check for firmware updates, or contact your ISP. For Mac-specific issues, reset network settings on your Mac via System Settings > Network > Advanced > Reset.

4. Can’t Boot From USB Drive 

If your Mac doesn’t boot from the USB drive, restart it and hold the Option ⌥ key to open the Startup Manager, showing all bootable devices. Use the arrow keys to select your USB drive and press Enter. If this fails, try resetting the SMC (System Management Controller) and PRAM (Parameter RAM) to fix the issue.

5. Installation Fails or Stops 

If your installation fails, pay attention to any error messages for clues on what went wrong. For more details, check the installation logs in /var/log/install.log on your Mac. When my installation stopped, a simple restart fixed the issue for me, so give that a try before attempting to reinstall again.

6. Required Space Not Available

Ensure you have enough disk space for the installation by checking under Apple menu > About This Mac > Storage. If space is tight, free up some space on your Mac. Also, disconnect external devices like USBs or hard drives, as they can interfere. If issues persist, consider alternative methods like a bootable USB drive or Internet Recovery.

7. Activation Issues

If you’re having trouble activating macOS, ensure your Mac is online. Check your Wi-Fi or Ethernet connection and troubleshoot as needed. Also, verify you’re signed in with the correct Apple ID used for the software purchase or activation, under Apple menu > System Settings > Apple ID. For App Store purchases, confirm they’re linked to the right Apple ID in the App Store > Purchased. If problems continue, reach out to Apple support for help.

Final Thoughts on Reinstalling macOS

Reinstalling macOS can improve your Mac’s performance, speed, and stability. Knowing how to reinstall macOS on your device is helpful, but learning about relevant steps can help you troubleshoot any issues. Here are some helpful tips:

• Before reinstalling macOS, double-check the macOS version system requirements to make sure it is compatible with your Mac.
• Prepare better for an update by learning how much space does macOS take on your Mac.
• If you’re interested, learn how to download old macOS versions and install them.

Frequently Asked Questions