How to Clean Install macOS Big Sur

Mac users may occasionally find themselves wanting to clean install macOS Big Sur onto a Mac. A clean installation of macOS Big Sur basically means the entire hard drive – including the system itself, all data, all apps, user accounts, literally everything – is erased, and then a fresh clean install of macOS Big Sur is installed onto the Mac. In this way it’s sort of like a factory reset or a fresh start, or what PC users sometimes refer to as reformatting, because there will be nothing left on the Mac at all, and booting it up will be similar to booting up a new Mac, with zero user data or other stuff.
A clean install is generally for advanced Mac users only, and is otherwise not recommended unless you’re giving away a Mac or transferring ownership, and have fully backed up your data. Because it erases the entire hard disk and all data on the Mac, it will cause complete data loss intentionally, so without sufficient backups the
Before proceeding, be certain you have a full backup of the Mac, and any or all important data. Failure to have sufficient backups will result in permanent data loss.

















