How to create a Windows 11 (or 10) bootable USB from macOS

• To create a Windows 11 USB installer from macOS, you’ll have to download the official ISO file, format a USB flash drive using the “diskutil” tool, split the “install.wim” file with the “wimlib” tool, and transfer the files to the bootable USB drive.

If you have to install Windows 11 (or 10) on a computer but only have a macOS device, it’s possible to create a bootable USB flash drive using a non-Windows machine, and in this guide, I will show how.

Although you have multiple methods to create an installation media for Windows 11, they are only available for Windows devices. However, it’s also possible to use macOS. The only issue is that the operating system only lets you format the USB storage using the FAT32 file system that can only store files less than 4GB when the “install.wim” file (containing the installation files) is usually larger than 4GB (usually 5.6GB). As a result, we have to resource third-party tools to split the image into two smaller files to complete the process.

In this guide, I will outline the steps to create a bootable USB using macOS to install Windows 11 as well as Windows 10.

Create Windows 11 (or 10) bootable USB using macOS

To create a bootable USB to clean install Windows 11 using macOS, use these steps:

1. Open the Windows 11 ISO download page.

2. Choose the Windows 11 option under the “Download Windows 11 Disk Image (ISO) for x64 devices” setting.

   

3. Click the Download Now button.

4. Select the installation language.

   

5. Click the Confirm button.

6. Click the “64-bit Download” button to save the ISO file on your macOS device, more specifically in the “Downloads” folder.

   

7. Connect a USB flash drive of at least 8GB of storage.

   Quick note: This process erases everything on the drive. As such, it’s recommended that any important data be backed up in the storage.

8. Open Launchpad.

9. Search for Terminal and click on the top result to open the command console.

10. Type the following command to identify the USB flash drive storage and press Return:

    diskutil list

    

    Quick note: In my case, the USB is identified as “disk4.”

11. Type the following command to clean and format the USB flash drive to make it bootable, and press Return:

    diskutil eraseDisk MS-DOS "Windows_USB" MBR disk4

    

    Quick tip: You can change “Windows_USB” to any name you want, but to avoid issues while running typing commands, make sure the name doesn’t include any space. I made that mistake and had to retype some of the commands because names with spaces have to be specified with quotation marks. Also, change “disk4” for the identifier of your USB flash drive.

12. Type the following command to open the “Downloads” folder where the ISO file is located and press Return:

    cd Downloads

13. Type the following command to mount the Windows 11 ISO file to macOS and press Return:

    hdiutil mount Win11_2xH2_English_x64vx.iso

    

14. Type the following command to transfer the installation files from the ISO file to the USB flash drive (excluding the install.wim file because it’s too large a FAT32 partition) and press Return:

    rsync -avh --progress --exclude=sources/install.wim /Volumes/CCCOMA_X64FRE_EN-US_DV9/ /Volumes/Windows_USB

    

15. Type the following command to install the Homebrew tool on macOS and press Return:

    /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

    

    Quick note: Homebrew is a package manager that will allow you to install the “wimlib” command tool to split the “install.wim” file and transfer it to the USB flash drive.

16. Confirm your macOS account password and press Return to continue.

17. Type the following command two commands to add Homebrew to your “PATH” and press Return on each line:

    (echo; echo 'eval "$(/opt/homebrew/bin/brew sheval "$(/opt/homebrew/bin/brew shellenv)"ellenv)"') >> /Users/YOUR-ACCOUNT/.zprofile
    eval "$(/opt/homebrew/bin/brew shellenv)"
    

    

    In the command, update “YOUR-ACCOUNT” to match the name of your macOS account.

18. Type the following command to install the wimlib tool and press Return:

    brew install wimlib

    

19. Type the following command to split the “install.wim” image and transfer the packages to the USB flash drive, and press Return:

    wimlib-imagex split /Volumes/CCCOMA_X64FRE_EN-US_DV9/sources/install.wim /Volumes/Windows_USB/sources/install.swm 3500

    

    Quick note: The “3500” number is the size in MiB of the file split. You can specify any number as long as it’s less than 4GB.

Once you complete the steps, you will end up with a bootable USB flash drive that you can connect to a computer to perform a clean install of the operating system.