To securely wipe and reinstall macOS, first back up data using Time Machine or cloud services, then enter Recovery Mode based on your Mac’s chip type, use Disk Utility to erase the startup disk with the correct format and scheme, reinstall macOS from the Recovery window, and finally choose whether to set up as new or restore from backup. Each step ensures a clean and secure reset.

If you're planning to sell, give away, or just reset your Mac, doing a complete wipe and reinstalling macOS is the best way to start fresh securely. It's not just about deleting files — you need to erase everything properly and reinstall the operating system from scratch.

Here’s how to do it step by step.

1. Back Up Your Data Before Wiping

Before you even think about wiping your Mac, make sure you’ve backed up all your important data. There are two common ways:

• Time Machine – Connect an external drive and let macOS automatically back up your files.
• Cloud services (like iCloud, Google Drive, etc.) – Upload key documents, photos, and settings if you don’t have an external drive.

If you skip this step, there’s no going back once the drive is erased.

Also, double-check that your backup actually contains what you need. Open the backup drive or log into your cloud account to verify.

2. Enter Recovery Mode to Start the Wipe

To wipe your Mac and reinstall macOS, you’ll need to boot into Recovery Mode. The steps vary slightly depending on your Mac’s chip:

• Apple Silicon (M1, M2, etc.):
  Turn off your Mac. Press and hold the power button until you see "Loading startup options." Then click Options > Continue.

• Intel-based Macs:
  Restart your Mac and immediately hold down Command R until the Apple logo appears.

Once in Recovery Mode, you’ll get a window with several tools. Choose Disk Utility first.

3. Erase Your Startup Disk Using Disk Utility

Inside Disk Utility:

1. Click View > Show All Devices in the top menu.
2. Select your main drive (usually labeled “Macintosh HD” or your Mac’s name).
3. Click Erase, then choose:
   • Format: Mac OS Extended (Journaled) for older macOS versions or APFS for macOS High Sierra and newer
   • Scheme: GUID Partition Map (important for Intel Macs)
4. Confirm and wait for the process to finish.

This completely removes all data, apps, and user accounts from your drive. Don’t worry if it takes a few minutes — it’s doing a deep clean.

4. Reinstall macOS After Wiping

Once the drive is erased, go back to the main Recovery window and select Reinstall macOS.

Follow the on-screen instructions. You’ll be asked to:

• Choose your Wi-Fi network
• Pick the disk you just erased as the installation target
• Wait while macOS downloads and installs — this can take 30–60 minutes depending on your internet speed

No need to log into an Apple ID unless you want to enable iCloud or App Store features later.

5. Set Up a Fresh macOS Without Restoring (Optional)

After macOS finishes installing, you’ll be greeted with the setup assistant. At this point, you have a choice:

• Set up as a new Mac – Don’t restore from backup if you’re giving it away or starting over.
• Or, if you want your old data back, you can use Time Machine or Migration Assistant to bring things over.

Just remember: once you set up a new user, the wiped state is gone for good (unless you repeat the process).

That’s basically it. A full wipe and reinstall doesn't require any special tools — just patience and a few clicks. It might seem like a lot, but each step is straightforward once you're in Recovery Mode. Just make sure you don’t skip backing up or rush through the erase process.

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