MacOS Big Sur ISO Image3-new
<https://www.wikigain.com/create-macos-big-sur-iso-image/>
In this article, I will show you how to create macOS Big Sur ISO image file. macOS Big Sur ISO is for [Installing macOS Big Sur on VMware](https://www.wikigain.com/install-macos-big-sur-on-vmware-windows-pc/) or Virtualbox. We have already created a step by step guide on how to [install macOS Big Sur on VirtualBox](https://www.wikigain.com/how-to-install-macos-big-sur-on-virtualbox-on-windows-pc/) and VMware. You need to be on a real Mac (aka [Macintosh](https://en.wikipedia.org/wiki/Macintosh)) or have macOS installed as VM.
If you don’t have a Macintosh then I recommended use the following guide and [install macOS Catalina on VMware](https://www.wikigain.com/install-macos-catalina-on-vmware-on-windows/).
Steps to Create macOS Big Sur ISO File
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1. Download macOS Big Sur From Apple
2. Create & Mount an empty Disk Image using hdiutil
3. Use the Createinstallmedia command to make the disk image bootable with macOS
4. Unmount the Disk Image
5. Covert the Disk Image to ISO image
**\#1.1.** There are 2-ways to download macOS Big Sur from Apple. If you have a developer account then visit developer.apple.com. Click on **Discover \> macOS \> Download**. Sign in with your developer account then scroll down and click the **Install Profile **button for macOS Big Sur Beta install. if you don’t a developer account then [download macOS Beta profile](https://betaprofiles.com/macos11) from **betaprofiles.com. **
[](https://g6k7x4j6.stackpathcdn.com/wp-content/uploads/2020/07/Download-macOS-Beta-Access-Uitility.png)
![[resources/2DFE7BF3A4EBA13F08C900874254DAA8.png]](assets/resources/2DFE7BF3A4EBA13F08C900874254DAA8.png)
Download macOS Beta Access Utility
**\#1.2.** After downloading the macOS Beta Access Utility.dmg open it. When the access utility window opens, Right-click on *macOS Beta Access* *Utility.pkg* then click **Open** \> **Continue \> Agree \> Install \> Enter your Password \> Install software** \> **Close. **
[](https://www.wikigain.com/create-macos-big-sur-iso-image/open-macos-beta-access-utility/)Open macOS Beta Access Utility[](https://www.wikigain.com/create-macos-big-sur-iso-image/install-macos-beta-access-utility/)Install macOS Beta Access Utility
![[resources/EE9F035E30071456AAC8F744EE9E9E6B.png]](assets/resources/EE9F035E30071456AAC8F744EE9E9E6B.png)
**\#1.3.** Finally, the Software Update window will open then you can start to download the macOS Big Sur directly from Apple’s server. So click **Upgrade Now** and wait for the download process to finish. It may take 10-20 minutes depending on your internet speed.
[](https://www.wikigain.com/create-macos-big-sur-iso-image/download-macos-big-sur-2/)Download macOS Big Sur[](https://www.wikigain.com/create-macos-big-sur-iso-image/downloading-macos-big-sur-beta/)Downloading macOS Big Sur
![[resources/F0D8CA9544B1718CA2CD26391C0EC2ED.png]](assets/resources/F0D8CA9544B1718CA2CD26391C0EC2ED.png)
**\#1.4**. When the download of macOS Big Sur is finished, make sure to quit the installer by click on **Install macOS Big Sur \> Quit Install macOS** or pressing **Command + Q**.
[](https://g6k7x4j6.stackpathcdn.com/wp-content/uploads/2020/07/Quit-macOS-Big-Sur.png)
![[resources/144C9E1F509CF4074FA99097B4C14399.png]](assets/resources/144C9E1F509CF4074FA99097B4C14399.png)
Quit macOS Big Sur
**\#2.1.** Once macOS is downloaded then Open **Terminal** and type the following command to create an empty disk image. Type your password when prompted.
sudo hdiutil create -o /tmp/BigSur -size 16384m -volname BigSur -layout SPUD -fs HFS+J
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**\#2.2.** Next, Mount the disk image to /Volumes/BigSur.
sudo hdiutil attach /tmp/BigSur.dmg -noverify -mountpoint /Volumes/BigSur
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**\#3**. Now will use the **Createinstallmedia command **to make the disk image bootable with macOS Big Sur.
sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/BigSur --nointeraction
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**\#4**. Unmount the Disk Image which is formatted from BigSur to Install macOS Big Sur and bootable with macOS Big Sur ISO image.
hdiutil eject -force /Volumes/Install\ macOS\ Big\ Sur
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**\#5** Covert and rename the Disk Image to ISO
hdiutil convert /tmp/BigSur.dmg -format UDTO -o ~/Desktop/BigSur mv -v ~/Desktop/BigSur.cdr ~/Desktop/BigSur.iso sudo rm -fv /tmp/BigSur.dmg
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[](https://g6k7x4j6.stackpathcdn.com/wp-content/uploads/2020/07/Creating-macOS-Big-Sur-Bootable-ISO-Final.png)
![[resources/77F467DFA942F230CF2A918A7932DFCB.png]](assets/resources/77F467DFA942F230CF2A918A7932DFCB.png)
Creating macOS Big Sur Bootable ISO
**Note:** running the *rm -rf* commands will do the cleanup and remove all the unnecessary file (disk image) from the /tmp folder. Although if you don’t do it then it will be automatically be removed after a while.
After running all the commands properly you should end up with a macOS Big Sur ISO image file on your Desktop.
[](https://g6k7x4j6.stackpathcdn.com/wp-content/uploads/2020/07/macOS-Big-Sur-Beta-4-ISO.png)
![[resources/BB35FCDA227E370A481D32992117A1E6.png]](assets/resources/BB35FCDA227E370A481D32992117A1E6.png)
macOS Big Sur ISO Image
Summary
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That’s all about how to install create macOS Big Sur ISO image file. We covered the following:
1. Download macOS Big Sur From Apple
2. Create & Mount an empty Disk Image using hdiutil
3. Use the Createinstallmedia command to make the disk image bootable with macOS
4. Unmount the Disk Image
5. Covert the Disk Image to ISO image
If I left out something and didn’t mention please let me know by commenting down belo
w this post. We have lots of new posts related to macOS Big Sur so stay up to date with us.