I need some good website recommendations on downloading the macOS DMG file for a bootable USB. I have a mid-2012 MacBook Pro. If you have the download links, it’s even better.
What macOS version are you looking for? The more recent macOS versions are not distributed as a DMG. But you can still find DMGs made from installers. You should find the download links of Mac OS DMG files from the resources below:
Thx a lot! I’m looking for the DMG file of macOS High Sierra. I’ll check out the resources later when I get home.
Why don’t you use the installer to create the bootable USB media? You can get the installers from the App Store.
My Mac doesn’t have an operating system now, so I can’t download the installer from the App Store. I’m trying to create a bootable installer from my Windows PC.
Very well. In this case, you’ll indeed need a standalone DMG download to make the bootable media on a Windows PC. I happen to know the steps to create a macOS bootable media on a Windows PC. I’ll list the simplified steps below and you can check out this full tutorial if necessary. (How to Create macOS Bootable USB from Windows 10/11)
- Prepare a USB external disk, the macOS High Sierra DMG file, and TransMac.
- Execute the following commands in Command Prompt to clean your USB drive and ensure it has the GPT partition scheme.
diskpart
list disk
Suppose disk 1 is your USB drive:
select disk 1
clean
convert gpt
If it tells you to select an MBR partition, your USB drive has the GPT partition map already. Just exist Command Prompt and continue with the next command.
create partition primary
exit
- Extract the BaseSystem.dmg file.
- Format your USB drive for Mac in TransMac and then restore the dmg file to it.
- Boot your Mac with the bootable USB.
Updated: macOS 15 Sequoia DMG