Click on it to create a new partition.įrom the new settings page, please give a name to new partitoon and choose Mac OS Extended Journaled)in Format tab. Right click the USB drive name at left sidebar and you will see Partition tab is visiable. Insert USB drive on Mac and open Disk Utility app from Spotlight. In the following example, we will create 3 partitions for macOS Big Sur, Catalina and Mojave, which are the most popular macOS release up to now. It depends on how many macOS versions to be kept on that USB drive. The first step is to create new partitions on external USB drive. How to Create a Multiboot macOS USB Installer on a Mac Make sure you're familiar with using these applications because they can impact your Mac at the system level.

Know how to use Disk Utility and Terminal on your Mac.

It's merely a question of checking whether partitioning is enabled and then setting it up for each of the macOS versions you want on the USB drive. If not, you'll need to do that before creating the installer.

Ensure that the USB is partitioned properly.However, you can download dmg file from other websites and put them on external USB drive to avoid taking free storage on your Mac. You need to download macOS install app on Mac, Each macOS installation app takes a plenty of free storage. A working Mac computers with enough free space.

To avoid this, try to get it from Mac App Store or a reliable third-party repository. As mentioned above, you may have some bloatware in the installer packages. Download macOS Installation app or DMG files for the versions of macOS you intend to put on this drive.For instance, third-party sources may have added some bloatware that increases the size of the file. The general practice is to always have a buffer of a few GB since OS sizes vary depending on the source. Get a USB drive (USB 3.0, fast reading and writing speed) with at least 10 GB free space for each macOS version.Requirementsīefore actually creating the multiboot USB installer, you'll need to take care of a few preparatory tasks: In short, if you want to run any macOS version on any computer, the multiboot macOS installer is a blessing in that sort of situation. Even running Mac on Windows is as simple as deploying VMs and putting multiple macOS versions on them. You can use these macOS versions on any Mac or PC by spending just a few minutes for the installation process. Quickly repair any version of macOS if you have multiple versions ready to use.You can have multiple macOS versions on VM in Windows using Parallels or a similar application.You can switch versions on the same computer by re-installing a different version of macOS.You can choose a macOS version when clean-installing on an older Mac.

How to install macos from usb