Creating a Bootable USB Flash Drive with macOS

This article describes the process of installing any* version of macOS (OS X) on a Mac. Including not only the creation of a bootable USB flash drive... but also links to download distributions and instructions for installing them.

It doesn't matter what OS version you have installed right now. You can download and install any version that is compatible with your Mac. The version of macOS that came with your Mac is the earliest version that it supports. For example, if you had macOS Big Sur installed on your computer, you won't be able to install macOS Catalina or earlier versions.

1. OS loading.

You can download macOS (OS X) from the App Store, but there are some restrictions that do not always allow you to do this... that's why we added the  OS Versions section

After downloading macOS, you need to mount the image and move the distribution (installer) to the Applications folder.

Please note that the distribution kit (installer) is located in the Applications folder. It is the distribution (.app), not the image (.dmg). And you don’t need to run anything here.

2. Creating a bootable USB flash drive (part 1).

You can use an external drive or an additional volume of at least 16 GB as a boot drive to install the operating system on your Mac.

Connect the USB drive used for the downloadable installer and launch Disk Utility.

Select the prepared drive and click Erase.

Fill in the fields as shown in the image below.

Name: MyVolume 
Format: Mac OS Extended (Journaled)
Scheme (if necessary): GUID Partition Scheme

Ready! Close Disk Utility.

Creating a bootable USB flash drive (part 2).

There are several ways to create a bootable USB flash drive, but we'll look at the best (but not the easiest) option using the createinstallmedia command in the Terminal application.

Make sure the USB drive used for the downloadable installer is connected and launch the Terminal utility.

Type or paste one of the following commands into the Terminal application. The installer is assumed to be in your Applications folder and the MyVolume name represents the USB drive or other volume you are using. Replace MyVolume with your volume name in the following commands.

Sonoma *:

sudo /Applications/Install\ macOS\ Sonoma.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Ventura *:

sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Monterey *:

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Big Sur *:

sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Catalina *:

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Mojave *:

sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

High Sierra *:

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Sierra :

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ macOS\ Sierra.app

El Capitan :

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app