Summary: It is advisable to back up all the data on the Macintosh HD before you implement the steps to erase the Big Sur or Catalina SSD volume.
FYI, Stellar Data Recovery Professional software helps you recover an accidentally erased Mac hard drive. Do consider this tool if you have erased your drive unknowingly.
Erasing macOS Mojave 10.14 Safely
Hope you have backed up the data safely to an external hard drive. Follow the sequences of steps to erase macOS Mojave SSD/HDD:
- Restart your macOS Mojave and press-hold Command and R keys simultaneously. Shortly, you will boot into macOS Utilities often known as Recovery Mode.
- You will be greeted with four option under macOS Utilities. Navigate to the Disk Utility out of the four provided options. Disk Utility mentions – “Repair or Erase a disk using Disk Utility.”
- In the Disk Utility windows, select your APFS Macintosh HD from the left corner and press Erase tab
- Select name and format for your storage drive and press Erase.
Warning: Erasing a Macintosh HD will remove your data stored on it. Once erased you can’t recover data without a data recovery software hence proceed with caution.
This is how you can erase your APFS start-up disk drive on macOS Mojave 10.14.