How to convert macOS installer.app to a bootable iso using terminal?

Converting a macOS installer .app file (e.g., Install macOS Monterey.app) into a bootable ISO using Terminal on macOS is a practical way to create a disk image usable in virtual machines like VirtualBox or VMware.

The process involves creating a temporary disk image, making it bootable with the createinstallmedia tool from the installer, and then converting it to an ISO format.

Below is a step-by-step guide using only Terminal commands, ensuring the resulting ISO is bootable

---

---

– What are the macOS systems that can be converted to iso images using this method : –
– the newer macOS.
– macOS Monterey    (Download).
– macOS Big Sur        (Download).
– macOS Mojave        (Download).
– macOS Catalina      (Download).
– macOS High Sierra (Download).

– Follow these steps for converting .app to .iso : –
0- you must copy the downloaded macOS.app installer into your desktop.

1- you have to ensure that you have enough disk space for running the full process.

2- Open terminal. using spotlight search type “terminal” and press enter. then start typing the following terminal commands:

3-Command 1: create a dmg container on the desktop of a size (15 BG) named “Monterey.dmg”: –

hdiutil create -o ~/Desktop/Monterey -size 15000m -volname Monterey -layout SPUD -fs HFS+J

4-Command 2: mount the Monterey.dmg container into your device: –

hdiutil attach ~/Desktop/Monterey.dmg -noverify -mountpoint /Volumes/Monterey

5-Command 3: Create a bootable macOS Monterey installer into the created dmg container  (N.B. You must have install macOS Monterey.app into your desktop as described before in step 2): – 

sudo ~/Desktop/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/Monterey --nointeraction

6-Command 4: detach the created bootable dmg container: –

hdiutil detach /Volumes/Install\ macOS\ Monterey

7- Command 5: Convert dmg to cdr container: –

hdiutil convert ~/Desktop/Monterey.dmg -format UDTO -o ~/Desktop/Monterey.cdr

8-Command 6: convert cdr to the bootable iso image: – 

mv ~/Desktop/Monterey.cdr ~/Desktop/Monterey.iso

NOW, you have created  a bootable Monterey.iso image that can be used with VirtualBox and other virtual machines.