How to Format External Hard Drive under OS X 10.10 Yosemite?

When your external hard drive is full of junk files, or you will resell your device, you may need to format it to regain the full storage or wipe sensitive data to avoid data leakage. Unlike Windows 10 or Windows 8, there is no direct option to format the device when you right-click the device under Mac OS X 10.10 Yosemite. However, there are still some easy solutions to format external hard drive under Mac OS X 10.10 Yosemite. Just follow the guide below, you can easily format the external hard drive under Mac OS X 10.10 Yosemite and wipe data.

Solution 1: Format External Hard Drive with Disk Utility under 10.10 Yosemite

Mac disk utility is a built-in application in all Mac OS versions including OS X 10.10 Yosemite. It can help users to format external hard drive under Mac OS X 10.10 Yosemite and erase all data. This solution is very simple. Here, you can follow these steps.

1. Connect your external hard drive with your Mac computer.

2. Open disk utility (click Launchpad – find disk utility).

3. Select the external hard drive and click "Erase".

Then disk utility will format the external hard drive.

This is a fast way to clean up all data on your external hard drive and format it. However, the formatted data can be recovered by data recovery software or other data recovery method because the data is not permanently lost. If you only want to format your external hard drive under Mac OS X 10.10 Yosemite or clean up all existing files, this solution is a good option. However, if you are going to sell/donate or throw away your external hard drive, this solution is not safe because it can’t permanently erase the data. Other people can easily recover your data from the formatted external hard drive. In order to permanently destroy all the data, the following solution will help you.

Solution 2: Format External Hard Drive with Super Eraser and Permanently Wipe Data

In some cases, people format an external hard drive before selling, donating or throwing away to avoid data leakage. In such cases, the data should be permanently destroyed. DoYourData Super Eraser for Mac is a powerful Mac data erasure application. It will help you format external hard drive under Mac OS X 10.10 Yosemite and permanently wipe data.

Just download and install DoYourData Super Eraser for Mac on your Mac computer. Then connect your external hard drive with your Mac. Now you can launch DoYourData Super Eraser for Mac to format external hard drive under Mac OS X 10.10 Yosemite.

Here are the steps: select Wipe Hard Drive mode.

Select the external hard drive and click on "Wipe Now" button.

Once the process gets started, all the existing/deleted/lost data on the external hard drive will be permanently destroyed and wiped. Nobody can recover it even with the best data recovery software. If you are planning to sell your external hard drive or just throw it to trash, you’d better use this solution to format your external hard drive under Mac OS X 10.10 Yosemite and permanently erase your data.