So you just got a new external drive and wanted to sell or give away your old one? Or your current external drive just got over-cluttered, and you want to completely wipe it out to regain all the storage space?
In this quick guide, you’ll learn two different ways to securely erase an external drive on a Mac computer.
Before you proceed, make sure you’ve already backed up all your important data. Once you use any of the methods below, the drive will be completely erased and all data will be removed permanently.
1. Using Disk Utility
First off, connect your external hard drive to a Mac. Make sure the device can be detected by the computer. Then follow the step-by-step tutorial below:
- On your Mac, go to Applications > Utilities > Disk Utility.
- Click on the Erase tab (next to “First Aid”).
- Select the disk or volume in the list on the left panel.
- Choose a file system to which you want to format your external drive.
- Next, click the Security Options button at the bottom.
- Here you can specify how securely you want to wipe the drive, move to Most Secure if you are paranoid because this option overwrites more times to the disk space, though the process tends to be slower.
- After that, click Erase to continue.
Note: If your drive is an SSD, you won’t be able to click “Security Options” as this option will be grayed out. It’s because SSDs don’t have to go through this process due to the way it manages files.
2. Via Terminal (Command Line)
If for any reason, Disk Utility fails to wipe your drive by showing errors like “unable to write to the last block of the device“.
You can try erasing the drive via the Terminal app, though it’s a command-line tool that requires you to be a bit geeky.
- Search “Terminal” in Spotlight.
- Open it and enter this line: diskutil list
- Now you’ll see a list of disks there, target yours through the disk identifier. Jot down the information.
- Next, type: diskutil eraseDisk JHFS+ (diskname diskidentifier)
- Press the Enter key and your external drive will be erased completely.
This video also has more:
Wiping an external hard drive clean on Mac is an easy task. With one of the above methods, you should be able to get the job done quickly.
If you have any questions during the process, let us know by leaving a comment below.