If Disk Utility shows a Security Options button in the Erase window, you can click that button to choose between a faster (but less secure) erase and a slower (but more secure) erase.If you can't start up from macOS Recovery, you can use a different startup disk instead.Reformat Apfs To Mac Os Extended Learn more Apfs To Mac Os Extended Journaled If you need help, please contact Apple Support. If your disk or volume still doesn't appear in Disk Utility, or Disk Utility reports that the erase process failed, your disk or Mac might need service.If you're erasing an external drive, make sure that it's connected directly to your Mac using a cable that you know is good.Shut down your Mac, then unplug all nonessential devices from your Mac.If your disk or volume doesn't appear, or the erase fails The Get Info window shows the Format of that volume. Select the volume in the Finder, then choose File > Get Info from the menu bar.The File System column on the right shows the format of each volume. Open System Information and select Storage in the sidebar.For more detail, choose File > Get Info from the Disk Utility menu bar. Select the volume in the Disk Utility sidebar, then check the information shown on the right.If you want to know which format is currently in use, use any of these methods:
How to identify the format currently in use Earlier versions of macOS don't work with APFS-formatted volumes. If the other Mac isn't using macOS High Sierra or later, choose Mac OS Extended (Journaled).
Are you about to install macOS High Sierra or later for the first time on the disk?.
If the built-in disk came APFS-formatted, Disk Utility suggests APFS. Are you formatting the disk that came built into your Mac?.If you want to change the format, answer these questions: If it can't, it chooses Mac OS Extended, which works with all versions of macOS. If you want your Mac to be able to start up from the volume you erased, reinstall macOS on that volume.ĭisk Utility tries to detect the type of storage and show the appropriate format in the Format menu.You might be asked to enter your Apple ID. Otherwise, click Erase to erase just the selected volume. In that case, you should erase the volume group. If you see an Erase Volume Group button, the volume you selected is part of a volume group.Name: Type the name that you want the volume to have after you erase it.The volume your Mac started up from is named Macintosh HD, unless you changed its name. In the sidebar of Disk Utility, select the volume that you want to erase.
If you're not erasing the volume your Mac started up from, you don't need to start up from macOS Recovery: just open Disk Utility from the Utilities folder of your Applications folder.