Changing the file system format for cross-compatibility.Resolving corruption or unreadable error of the storage drive.Preparing the startup disk to reinstall macOS.You may even need to manually format your internal or external Mac storage drive or volume in the compatible file system. MS-DOS (FAT) or exFAT format to make your external storage drive cross-compatible with both macOS and WindowsĪ new Mac with its built-in solid-state drive or hard drive comes pre-formatted with a file system that contains the macOS.Mac OS Extended format for macOS Sierra 10.12 or earlier.APFS format for macOS Big Sur 11, Catalina 10.15, or Mojave 10.14.Different file system formats exist for different operating systems. Recover Data Lost due to Accidental FormattingĪn internal or external Mac storage drive requires compatible files system format to be accessible in macOS. Format a Mac External Hard Drive Using TerminalĤ. Format the Startup Disk in macOS Recovery Modeģ. Back Up Your Mac Hard Drive before FormattingĢ.
