Use whatever SD card adapter you have to connect your SD card to your computer.

Navigate to Applications > Utilities > Terminal.

Enter the following command to find your SD card’s name:

diskutil list

You can identify your card by size and partition type. You should see the Raspberry Pi boot partition type of Windows_FAT_32 next to the drive.

For example, my card’s name is /dev/disk2.

Use the following command to use the dd utility to backup your Raspberry Pi SD card, changing /dev/disk1 to your disk’s name and path:

sudo dd if=/dev/disk1 of=~/PiSDCardBackup.dmg

Enter your password when prompted.

This will create a file named PiSDCardBackup.dmg in the user directory (~). To change the filename or put it somewhere else, you can change ~/PiSDCardBackup.dmg to something else. For example, ~/Documents/OctoPrint.dmg will name the file OctoPrint.dmg and place it in your Documents folder.

While the backup process is running, you should just see a flashing | indicator.

Don’t forget to safely eject your card before removing it from your computer to prevent data corruption. You can do this in Finder by clicking the eject icon in the sidebar. You’re all done!

To restore your backup or clone it onto another SD card, reinsert it into your computer and use the following commands:

diskutil unmountDisk /dev/disk1
sudo dd if=~/PiSDCardBackup.dmg of=/dev/disk1

Be sure to replace /dev/disk1 once again with your card ID, and specify the proper location for the backup image you’re restoring from.

When you’re finished, eject your SD card once more.