How to Create a Bootable USB for Mac: A Step-by-Step Guide

Are you looking for a way to create a bootable USB drive for your Mac? Look no further! In this article, we will guide you through the process of creating a bootable USB installer for macOS Big Sur, Catalina, Mojave, and High Sierra.

Before You Begin

Before you start, there are a few things you need to keep in mind. First, make sure you have nothing stored on the USB drive you plan to use. It is also important to note that the `createinstallmedia` command erases everything on your external USB drive.

Step 1: Connect Your USB Drive

Connect your USB thumb drive or any other external volume to your Mac system. Make sure it is formatted as macOS Extended and has a storage capacity of at least 14 GB.

Step 2: Launch Finder and Open Disk Utility

Launch the Finder from the Dock and open Disk Utility from the Applications section. If you are using High Sierra or later, click the View button on the top left corner and select Show All Devices from the dropdown menu. Alternatively, press Command + Spacebar to open Spotlight search and type Disk Utility to find and open it.

Step 3: Download the macOS Installer File

To create a bootable USB installer for Mac, you need to first download the macOS installer file. You can use the App Store or the Apple website to download the installer file. Follow these steps:

* If you have macOS Catalina, click on the Software Update button in System Preferences > Software Update.

* Select 'Download macOS Big Sur' and follow the prompts to download the installer file.

* The installer file will start downloading and will be saved to your Applications folder as an app named Install macOS Big Sur/Catalina/Mojave/High Sierra.

Step 4: Create Bootable USB Installer

Once you have downloaded the installer file, you can use the `createinstallmedia` command to create a bootable USB installer. Open Terminal and insert the relevant command with utmost caution.

For example, if you are using macOS Big Sur, the command would be:

```

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

```

Replace `/Volumes/USB` with the name of your USB drive.

That's it! With these simple steps, you can create a bootable USB installer for macOS Big Sur, Catalina, Mojave, and High Sierra. This bootable USB installer allows you to perform a clean install of macOS, install macOS from USB on a separate volume of your Mac drive, or in case your Mac encounters OS issues.

Create mac os bootable usb