Format or reformat a storage device for Mac  9-2023

Steps for preparing a hard drive, SSD or flash drive for storing data, making a back up 

or using for Time Machine. 

1.Connect your storage device to your Mac. Check that it shows up on your DeskTop. Note: it’s best 

to connect directly to your Mac not to a hub or dock if possible. 

2.Launch Disk Utility application. It is found in your Utilities folder inside your Applications folder. 

3.In Disk Utility, click on the icon above the word View and select Show All Devices. 

4.In the side bar on the left side click on your device. Click the top icon for the device, that is the 

actual device not just a volume on the device. 

5.On the right hand side at the top click Erase. 

6.Name field, give the device a name. 

7.In the Format field what you choose depends on the device and the Mac OS you are using. Newer 

OSs use APFS, older OSs use Mac OS extended. Flash drives use Mac OS extended. New Macs 

can read and write to Mac OS extended drives and devices, but APFS is Apple’s preferred format 

going forward. If you are using the last two (or the about to be released) Mac System Software, 

choose APFS. 

8.In either case above in the Scheme field choose GUID partition map. 

9.Click the Erase button in the lower right. 

10.Disk Utility will start the format process. It should not take very long, but larger drives take longer 

as you might expect. Be patient. You can see a progress list if you click Show Details. Disk Utility 

will unmount the device, do its thing and when finished remount the device with the name you 

entered. It will read Done. 

11 .The device is now ready to use. 

12.Piece of cake, right? 

If you want to use a flash drive in your car or on your TV you need to format it for Windows. 

Name Field, use short name 8 characters or less. 

Format Field chose FAT 32 

Scheme Field chose Master Boot Record 

There may be some newer cars or TVs the can read APFS, but all should be happy with FAT 32. 

© Terrance Crooker 2024