You create such an encrypted image this way: But you have the option to add another 4GB of data to it. If you put only 1GB of data in it and check its file size, you will see that it’s approximately 1GB in size. So, for example, you can create a sparse image that will hold up to 5GB of data. Sparse images are images of a user-determined size that consume only as much storage as is used by the content in the image. If you don’t and someone sits down at your computer when it’s logged into your account, they can open the image simply by double-clicking on it. You’ll also see the Remember Password in My Keychain option. (If you’re very concerned about security you can choose 256-bit AES Encryption, but as the parenthetical advises, this is more secure but takes longer to encrypt.) If you’re concerned about the amount of space the image might consume, you can choose Compressed from the Image Format pop-up menu, but the image will take a little longer to create.Ĭlick Save and Disk Utility will prompt you to enter and verify a password. In the resulting window select Read/Write from the Image Format pop-up menu and 128-bit AES Encryption (Recommended) from the Encryption pop-up menu. In the Select Folder to Image window that appears navigate to the folder you’ve created. Choose File -> New -> New Disk Image From Folder. Create your folder full of documents and launch Disk Utility (/Applications/Utilities).

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