If you don’t want to proceed with partitioning the disk, click Cancel.Īfter the operation finishes, click Done.Īfter you partition a storage device, an icon for each volume appears in both the Disk Utility sidebar and the Finder sidebar. If you want to proceed with partitioning the disk, click Continue. If a dialog appears that indicates it will take a long time to resize the startup volume, read the information in the dialog, then do one of the following: Read the information in the Partition Device dialog, then click Partition. Type a name for the volume in the Name field.įor MS-DOS (FAT) and ExFAT volumes, the maximum length for the volume name is 11 characters.Ĭlick the Format pop-up menu, then choose a file system format.Įnter the size or drag the resize control to increase or decrease the size of the volume. First, one can go to Finder > Go > Utilities, then double-click on the Disk Utility icon. Launching Disk Utility Disk Utility can be launched several different ways.
Otherwise, you can skip this step and do it from the Utilities page during the macOS or OS X installation. During the macOS Sierra beta, my test machine was partitioned with Mac OS X El Capitan on one partition and macOS Sierra beta on another. If your Mac doesn’t work, you can do this using a second Mac and an external hard drive caddy. It’s easy to reformat your hard drive using Disk Utility in macOS or OS X. The only disk available to Reinstall OS X Yosemite however when I tried is ask to select the disk where I want to install OS X and no option to Install and move forward with the installation. Locate the app 'Disk Utility' from the apps available on the 'Utilities' folder. The Disk Utility shows the first disk on the left APPLE HDD HTS541010A9E662 Media and under says disk0s2, the second disk is disk1 OS X BASE SYSTEM. Go to the 'Applications' and then 'Utilities'.
Just follow the steps below to burn ISO files to USB/DVD on Mac OS X. Note: If you click Add Volume instead, you can click the Add button to create an additional APFS volume in the container, or click Cancel to return to the Disk Utility window without making any changes to the storage device. Disk Utility can be used to format external drives as well. It comes pre-installed with the Mac OS so you dont have to worry about its downloading and installation.