How to quickly create a macOS bootable USB on Windows 10

UPDATED 8/29/2023: It doesn’t matter whether you use macOS, Windows 11, or Windows 10. It’s a matter of time until the device refuses to start, which could happen for many reasons, including (but not limited to) file corruption, hardware failure, or buggy update. If the unexpected happens with an Apple computer, you can resolve the problem using a macOS bootable USB with the installation media.

This is one of the main reasons you should consider creating a macOS bootable USB when your computer is working correctly. However, if none of your devices (MacBook, MacBook Air, MacBook Pro, iMac, Mac Pro, or Mac Mini) are not working when you need them the most, it’s possible to use a Windows computer to rescue your Apple device. You can use a Windows 11, 10, 8.1, or 7 computer to quickly create a USB bootable installation media to reinstall macOS Ventura, Monterey, Big Sur, Catalina, or Mojave on your Mac.

This guide will teach you the steps to create a macOS bootable USB installation on Windows 10 (or 11), which you can use to reinstall or upgrade the Apple OS.

Requirements
Create macOS bootable USB installation media
Create a GPT partition on a USB flash drive

Requirements

To perform this task, you’ll need:

Broken Mac computer running macOS.
A trial copy of the TransMac software.
One high-quality USB flash drive with 16GB of storage.
Copy of macOS (DMG file).

Create macOS bootable USB installation media

To create a bootable USB drive with macOS, use these steps:

Download and install TransMac on Windows 10.

Quick note: This is a paid piece of software, but it gives you a 15-day trial, which is more than enough time. (If this works and you want to support the developer, purchase the full version.)
Connect the USB flash drive.

Important: If you have any data on the flash drive, remember to back it up since this process will erase everything on it.
Right-click the TransMac app and select the Run as administrator option.
Click the Run button. (If you use the trial version, wait 15 seconds.)
Right-click the USB flash drive and select the “Format Disk for Mac” option from the left pane.

Quick note: You want to perform this task before creating the bootable media because there is a good chance that the drive was formatted using a Windows device. If this is the case, the chances are it’s using an MBR partition, and the USB drive needs a GPT partition to work on a Mac.
Click the Yes button to format the drive on the warning message.
Confirm a name for the drive. For example, “macOS bootable USB.”
Click the OK button.
Click the Yes button.
Click the OK button.
Right-click the USB flash drive and select the “Restore with Disk Image” option from the left pane.
Click the Yes button to confirm the erase of the USB flash drive data.
Click the browse button on the right.
Select the “.dmg” file with the macOS installation files.
Click the Open button.
Click the OK button.
Click the Yes button.

Once you complete the steps, insert the USB flash drive on your Mac to install, reinstall, or upgrade the operating system to the latest macOS version (Ventura, Monterey, Big Sur, Catalina, or Mojave).

Create a GPT partition on a USB flash drive

If the USB flash drive is not working with TransMac, it could still be a partition problem. In this case, you may need to redo the entire process. However, this time, you should follow these steps to use the Diskpart command-line utility on Windows 10 (or 11) to create the appropriate GPT partition, and then follow the above instructions.

To create a GPT partition on a removable drive, use these steps:

Open Start.
Search for Command Prompt, right-click the top result, and select the Run as an administrator option.
Type the following command and press Enter:
```
diskpart
```
Type the following command to view all drives connected to your computer and press Enter:
```
list disk
```
Type the following command with the number assigned for the USB flash drive and press Enter:
```
select disk 4
```
In the command, change “4” to the number corresponding to the USB flash drive.
Type the following command to clean the drive and press Enter:
```
clean
```
Type the following command to convert the drive to the GPT style and press Enter:
```
convert gpt
```
Type the following command to create a primary partition and press Enter: create partition primary
```
create partition primary
```

Once you have formatted the USB flash drive with a GPT partition, you can use the instructions mentioned above to use TransMac to create a bootable media, but this time, skip steps 5 through 10 and continue on step 11.

After the process, which could take up to an hour, connect the USB flash drive, turn on your Mac by holding down the “Option” key, and select the USB drive to install macOS.