How to Run macOS Catalina Alongside Mojave?

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macOS Catalina is the latest release in the macOS series. With its launch come plenty of user-friendly features, including the ability to use your iPad as an external screen, and the ability to regulate app usage through the amount of screen time it takes. Perhaps the most notable change is the replacement of the iTunes app with three different apps: Apple Podcast, Apple Music, and Apple TV.

Speaking of macOS Catalina, it is almost a year since Apple declared its intentions to make it easy for developers to move iOS apps over to Mac. The company fulfilled the promise with the release of macOS Catalina, which allows users to run iPad apps on their Macs.

macOS Catalina Public Beta

If you are excited about the launch of Catalina and can’t wait to try it, you can join Apple’s Beta Software Program. This way, you get to test the cool features of macOS Catalina before Apple ships it this fall. Unfortunately, Catalina is only available through a beta version.

Some people may be hesitant to try the beta version of Catalina because they fear it might cause inconvenience and mess up their workflow. The good news is that updating to the new version of macOS doesn’t have to be an all-or-nothing affair. You can still run Catalina and Mojave together. In this article, we will show you how to run the two versions of macOS on a Mac.

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But First, Why Dual Booting Is a Good Idea?

There are many reasons you might want to run two versions of macOS on a Mac, but here are the key ones:

  • First, you have to use your Mac to carry out your other daily activities, but you still want to try the new OS. With dual booting, you can test the new macOS version without interfering with your workflow. If it turns out to be stable, you can get rid of Mojave without unnecessary pauses.
  • Updating to the latest operating system can be a challenge if you have legacy apps that are not compatible with it. So, dual-booting is a smart idea if you need to run those apps.
  • Apple has only provided a beta version, so you don’t have another choice.

While Catalina brings lots of improvements, its hardware requirements are still the same as for Mojave. So, any Mac built after 2012 will support the new macOS version. But if you are curious, here are the Mac models that are compatible with the new operating system:

  • MacBook Air 2012 or later
  • MacBook 2015 or later
  • MacBook Pro 2012 or later
  • MacBook Pro 2013 or later
  • iMac 2012 or later
  • iMac Pro 2017 or later
  • Mac Mini 2012 or later

How to Run Catalina and Mojave Side-by-Side?

If your Mac is compatible with macOS Catalina, follow the steps below to dual boot Catalina and Mojave on your Mac:

Step 1: Initial Preparations

Back Up Your System

Once installed, macOS Catalina will have access to all the files on your Mac, so back up all your important files just in case anything goes wrong. Preferably, create a backup of your Mac before you even download the latest OS.

Clean Your Drive

The other thing you need to do is to create space for the new macOS version. To do that, delete all the junk in your system. The more space you have, the better. Start with removing unnecessary apps, files, and folders. You may also need to transfer your photo library into an external disk.

Doing all these can be time-consuming, and there is also the risk of deleting crucial system files. Taking this into account, we recommend the Mac repair app tool for this purpose.

Consider Installing macOS Catalina on an External Hard Drive

If wiping up your system sounds too risky, then you can try installing the new version of macOS on an external hard drive.

Step 2: Create a New Volume

For it to run, macOS Catalina will require its own partition on your hard drive. If you are running Mojave or High Sierra, this process is straightforward, as your computer will use the new Apple File System. If your startup disk is not formatted as APFS, it is much better to install macOS Catalina via an external hard drive. With that said, let’s go ahead and create a new partition for macOS Catalina:

  1. Open the Disk Utility program by going to Finder > Applications > Utilities, then choose Disk Utility.
  2. Once the Disk Utility opens, click on the drop-down menu next to the View button and select Show All Devices.
  3. Choose the hard drive you want to partition, and then click on the plus (+) icon in the toolbar to create a new partition.
  4. Give your new partition a name.
  5. You also need to set the storage limit for this partition. Allocate about 25GB – 100GB for it, and then format the partition as APFS.
  6. After that, click Apply to save the changes.

Now, you have a new volume ready to install the beta version of macOS Catalina.

Step 3: Download and Install macOS Catalina

Now that you have a new partition, your next step is to download and install macOS Catalina on the newly created volume. To do that, follow the steps below:

  1. To download Catalina, you first need to enroll for Apple’s Beta Software Program. You do so by signing into the program with your Apple ID.
  2. Once you have done that, download the macOS Public Beta Access Utility.
  3. Wait for the OS to download. When the download starts, you will be prompted to select a location for the installation. Select the volume you just created above.
  4. When the download finishes, install the new OS.

Step 4: Dual Boot Catalina Beta and Mojave

Once you have installed macOS Catalina on your Mac, the remaining task is to choose the version of macOS to boot into. Here is how to do it:

  1. As you restart your Mac, press and hold down the Option Key, and then choose either Mojave or Catalina.
  2. Before you restart or shut down your computer, head to the Apple menu, and then select System Preferences. After that, choose Startup Disk and pick the OS you want to boot into next time.


Running two versions of macOS on the same Mac isn’t for everyone. But that doesn’t mean it is difficult to do. It is a perfect way to try the beta version of macOS Catalina, while still running Mojave. With the help of this guide, you should be running both versions of the operating system in no time.

Share with us your experience of running the two versions of macOS on a Mac.

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