How to Make a Bootable Mac ISO

Data files with the .iso extension act as disk image files, which can be burned onto a blank CD or DVD and used as bootable media. Even though .iso files are used primarily with the Windows operating system, you can make them on a Mac with the Disk Utility application. Disk Utility is a tool included on all new Apple computers running Mac OS X.

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You can create bootable .iso files in Disk Utility on a Mac.

Step

Launch the Disk Utility application on your Mac computer. The program can be found within the "Utilities" folder in the "Applications" section of the hard drive.

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Highlight the existing image or disk that you want to use to create the .iso file from the list of media items on the left side of the window.

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Go to the "Images" menu at the top of the window and select the "Convert" option.

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Select "DVD/CD Master" from the "Image Format" drop-down menu.

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Click on the "Save" button to begin creating the image file. By default, Disk Utility will give the image file an extension of .cdr.

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Change the extension of the new image file from ".cdr" to ".iso" and hit "Enter" to save the changes. This creates a working .iso file, which you can burn to a CD or DVD and use as bootable media.