Below we’ve covered how to open a DMG file on a Mac and, subsequently, how to use a DMG file to install an app on your Mac. But before we get to that, let’s talk a bit more about DMG files.
What Is a DMG File?
An Apple Disk Image file, commonly known as a DMG file, is a mountable disk image primarily used to distribute software on the Mac. DMG files are widely used as they are easy to mount on macOS and can store a compressed software installer.
DMG files are primarily used for distributing and installing software on a Mac outside the App Store. You can also think of a DMG file as Apple’s version of an ISO file.
DMG files are designed only to be used on Macs and, therefore, aren’t natively compatible with Windows. Similarly, as DMG files contain installers for macOS, opening one on Windows won’t be useful. So, if you want to install the same app on a Windows PC, you’ll need to download the Windows installer from the manufacturer.
How to Open a DMG File on a Mac
By default, macOS does a good job opening DMG files, and no additional software is required. All you need to do is double-click the DMG file to open and mount it to your Mac.
Once you do this, you should see the DMG file pop up in the Finder sidebar as a mounted disk. Alternatively, you’ll also see the DMG file on your desktop. Clicking on this will open up the DMG file.
Inside the DMG file, you should see the application itself and a shortcut to the Applications folder. Drag the app to the Applications folder to install it.
What to Do if the DMG File Doesn’t Work?
A DMG file is a prevalent distribution format because it uses checksums to make sure that the DMG file’s integrity hasn’t been damaged before opening it on your Mac.
In the rare case a DMG file doesn’t work, it may be a matter of simply downloading the DMG file again, as the download may have been uninterrupted.
If it still doesn’t work, it’s worth contacting the developer to let them know that the DMG file isn’t working, and they might be able to provide an alternate installer.
Make Sure You Use Trusted DMG Files Only!
Although DMG files are a good means to distribute software among macOS users, we still recommend making sure you only download DMG files from trusted developers.
This will go a long way in ensuring your Mac doesn’t suffer from any malware attack through an infected installer and will help maintain the security of macOS.
