If a hacker gets a hold of your file, they can try to use a brute-force attack to determine the password. Make sure you enter a very long and strong password because this is the only security that protects your data. When you choose any of the encryption options, you’ll be asked to enter a password. The latter will be slower because of the stronger encryption, but your data will be better protected. Under Encryption, you can choose from 128-bit or 256-bit AES encryption. You’ll now have to choose the folder that you would like to encrypt as a disk image.Ĭlick Open and you’ll get the Save As dialog where you have to give your new image a name and choose from a couple of options.īy default, it’ll save the new disk image in the same folder that you are encrypting. Once Disk Utility is open, go ahead and click on File – New Image – Image from Folder. To get started, go ahead and open Disk Utility by going to Applications or by clicking on the Spotlight icon (magnifying glass) at the top right and typing in Disk Utility. Note that once you create the disk image, the original unencrypted folder will still remain on your system and you should delete it immediately.

To create the disk image (DMG) on your Mac, first create a folder that includes all the data you want to encrypt.

Mac disk image size