How to encrypt a folder in MacOS to keep sensitive data from prying eyes
You probably have sensitive data on your MacBook or iMac. This data may be in a folder containing various files containing company secrets or your own personal information. Unencrypted, this folder can be viewed by anyone with access to your desktop or laptop.
However, if you encrypt this folder, only those with the decryption password can access the contents inside.
You can achieve folder encryption using a third-party application, but there is also a built-in tool that can do it for you. This tool is Disk Utility and makes encrypting existing folders on your macOS computer very easy.
The limitation of the method I’m going to outline is that it creates an encrypted image from the folder and leaves the original intact. In addition, once you create the encrypted image, you cannot add new items. For this reason, the method is best suited for encrypted backups or for encrypting folders that do not need to be modified.
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How to encrypt a folder in macOS to protect sensitive data from prying eyes
Let me show you how it’s done.
requirements
All you need is an updated version of MacOS running on either a MacBook or iMac. I will demonstrate on a MacBook Pro with an Apple Silicone M1 chip and MacOS Monterey (v 12.6). I would strongly recommend that you test this process on a folder that does not contain any important documents. Once you know how to successfully encrypt folders, you can do it with the folders that contain important information.
Click the Launchpad icon in your Dock and type Disk Utility. When the Disk Utility launcher appears, click on it to open the app.
With Disk Utility open, click File > New Image > Image from Folder. When the folder selection popup appears, navigate to the folder you want to encrypt, select it and click “Choose”.
Creating a new encrypted image from a folder in MacOS. Jack Wallen/ZDNET
In the resulting pop-up window, do the following:
- Name the encrypted folder.
- Add any tags you want to include.
- Choose either 128-bit or 256-bit encryption (the latter is stronger).
- Click on “Save”.
When you select the encryption type, you will be prompted to enter and confirm an encryption password. Make sure this password is strong and unique (and not the same as your user password).
Disk Utility then encrypts the folder. When complete, click Done.
Be sure to give your new encrypted image a unique name. Jack Wallen/ZDNET
How to access files in the encrypted image
Open Finder and navigate to the folder where the encrypted image is located. If you double click on this image (it ends with .img) you will be asked for the password you added during image creation. After successful authentication, Finder opens the image and you can access the content inside.
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And that’s all you need to create an encrypted folder in macOS using Disk Utility. Although this option is somewhat limited, it’s a good way to protect sensitive information from prying eyes. And if you don’t need to add new files and folders to the encrypted image, you can delete the original folder so that the data inside is inaccessible without going through the encrypted image.