🔧 How to Erase & Reinstall macOS Using Option + Command + R (Full Guide)

If your MacBook’s feeling sluggish, you’re swapping out the hard drive, or just want to start fresh, doing a clean macOS install is the way to go. In this post, I’ll walk you through how to format your drive and reinstall the latest compatible version of macOS using Internet Recovery Mode (with the shortcut Option + Command + R).

Whether you're prepping to sell your Mac or fixing a software issue, this method gives you a clean slate.

🧰 What You’ll Need

• A reliable internet connection (Wi-Fi or Ethernet)

• A backup of any important files (Time Machine, iCloud, or external storage)

Note: This process will erase everything on your drive, so double-check your backup before proceeding!

🔄 Step 1: Boot Into Internet Recovery Mode

1. Shut down your Mac completely.

2. Turn it back on and immediately hold Option + Command + R.
   Keep holding until you see a spinning globe 🌐 or the "Starting Internet Recovery" screen.

3. Connect to your Wi-Fi network when prompted.

Your Mac will now load macOS Recovery tools from Apple’s servers. This might take a few minutes depending on your connection.

💽 Step 2: Format the Drive Using Disk Utility

1. Once the recovery tools load, choose Disk Utility from the list and click Continue.

2. In the sidebar, select your internal drive (usually called Macintosh HD).

3. Click Erase at the top.

4. Use the following settings:

   • Name: Macintosh HD (or whatever you like)

   • Format: APFS (recommended for macOS 10.13 and later)

   • Scheme: GUID Partition Map

5. Click Erase to wipe the drive.

After that’s done, close Disk Utility to return to the main macOS Utilities menu.

🖥️ Step 3: Reinstall macOS

1. From the main menu, choose Reinstall macOS.

2. Click Continue and follow the prompts.

3. Select the drive you just erased (Macintosh HD).

4. Sit back while macOS downloads and installs. This part can take 30–90 minutes depending on your internet speed. Your Mac will restart several times during the process.

✅ After Installation

Once macOS is reinstalled, your Mac will boot to the setup assistant where you can:

• Connect to Wi-Fi

• Sign in with your Apple ID

• Restore data from a backup (optional)

From here, you’ve got a fresh system, just like new.

📝 Final Tips

• Don’t forget to update macOS after setup via System Settings → Software Update

• If you’re selling or giving the Mac away, stop at the setup screen so the new owner can set it up as their own

• For older Macs, Option + Command + R may not work. Try Command + R or Shift + Option + Command + R instead

Need help upgrading your SSD or backing up data before you start? Feel free to reach out or drop your questions in the comments.