Many of us rely on external USB drives and storage devices, whether hard drives or flash drives, to transfer large files and to serve as backups for things like Time Machine. Typically when you buy a new hard drive or USB drive, even if for a Mac, it comes pre-formatted in a Windows friendly format like exFAT or FAT32, rather than Mac file system like HFS+. This isn’t a problem however, as you can easily format a USB drive to be fully Mac compatible.
The process to erase and format a a USB drive is the same regardless of whether the drive is a USB hard drive, USB flash drive, SSD, key, thumbdrive, or otherwise, and it’s also the same regardless of whether or not the drive is USB-C or USB-A.
It’s important to remember that formatting a drive will erase all data on the drive, so you will not want to do this if you have data on the drive that you wish to preserve.
How to Format an External USB Drive on Mac
Formatting will erase everything on the drive to make it natively compatible with MacOS.
- Connect the USB drive to the Mac
- Open Disk Utility on the Mac from /Applications/Utilities/ or with Spotlight
- Select the USB drive you want to format from the left sidebar
- Click the “Erase” button in the toolbar
- Give the drive a name if you’d like to, like ‘backup’ or whatever, and if you want native Mac compatibility then choose “MacOS Extended (Journaled)” as the file system type, then click on “Erase” *
- Let Disk Utility erase the drive, depending on the type of disk this may either be very quick or take some time, but be patient until it finishes
- When finished, click “Done” and put the drive to use as intended
Now you’re ready to use the formatted USB drive on your Mac for whatever purpose, whether that’s to use as a Time Machine backup drive, a destination for manual file backup, extra storage space, run an operating system directly from, or whatever else you’d like to do.
* You may have noticed you can also choose other file system types when formatting a USB drive on the Mac, but for most Mac users they’ll want to stick with Mac OS Extended. You can also pick FAT and exFAT formats, however, if you want the drive to be compatible with Windows as well as MacOS.
Formatting any USB drive for the Mac is the same regardless of whether it’s a USB flash drive, USB external SSD drive, USB key, a traditional spinning USB HDD drive, or whatever other external drive or disk you have. This process is basically the same in all versions of MacOS too, so regardless of what system software the Mac is running you will find these instructions are applicable.
Did you successfully format a USB drive to work with a Mac? Did you run into any issues? Let us know your experiences, share your thoughts, or ask whatever questions you may have in the comments below.