Each year that Apple releases a major new version of macOS, a few older Mac models that ran the previous version usually fail to make the new list of officially supported Macs. In the case of Catalina, the latest macOS version, the operating system doesn't work on models released before mid-2012 (and Mac Pros before late 2013).

Catalina
Apple's official list of Macs supporting macOS Catalina:

To check if your Mac is compatible, open the Apple () menu in the upper left corner of your Mac's screen and select About This Mac. Look just below the OS X version number in the Overview tab – if the Mac model name is the same or a later model year than the one shown in the compatibility list above, your Mac is compatible with macOS Catalina.

What You Can Do if You Have an Unsupported Mac

If your Mac is too old to make it onto the above list, Apple has decided that it lacks the hardware required to meet the demands of Catalina. But that doesn't mean there's no way that you can get it running.

macos catalina patcher
DosDude Catalina Patcher is a popular third-party tool that allows users to patch the MacOS Catalina installer on otherwise unsupported Macs. Of course, just because you can do this, doesn't mean you should, as there's a good chance that performance will be sub-optimal, while Catalina features may depend on modern Mac hardware (Sidecar, for example) and likely won't work at all.

Despite these risks, if for whatever reason you're still interested in installing macOS 10.15 Catalina on older unsupported hardware, these steps should get you up and running. You can find a compatible list of unsupported Macs for Catalina Patcher on the DosDude website.

How to Use Catalina Patcher on Older Macs

Before you proceed with these steps, ensure that you have an up-to-date backup of your Mac. Attempting to install Catalina on an unsupported Mac is in no way supported by Apple, and you are doing so at your own risk. MacRumors cannot be held liable for any data loss or damage as a result.

  1. Download the latest version of the Catalina Patcher by DOSDude1.
    macos catalina patcher url

  2. Right-click the Catalina Patcher app and select Open.
    1catalina patcher tool

  3. Click Continue twice.
  4. Select Download a Copy.
    2catalina patcher tool

  5. Click Start download. It's over 7GB, so you'll have to wait a while for it to complete.
    3catalina patcher tool

  6. Connect a USB flash drive (formatted as MacOS Extended Journaled) into your Mac and select Create a bootable installer from the three Installation Method options.
    4catalina patcher tool

  7. Select your flash drive volume from the list and click Start.
  8. When the installer is complete, restart your Mac and hold down the Option key when the reboot tone sounds.
  9. Select your USB drive installer from the boot list.
  10. If your Mac is currently running a version of macOS that predates High Sierra or Mojave, you'll need to format your hard drive to APFS before installing Catalina. To do this, select Disk Utility, choose your system volume and click Erase, then select the APFS format. If you don't need to do this, simply select Reinstall macOS from the macOS Utilities window and follow the steps to install the new version of macOS on your Mac.
    macos high sierra recovery mode reinstall

  11. Allow the installation to proceed and the relevant patches will be applied to your unsupported Mac automatically.

Apple could always release a future update to macOS 10.15 that prevents the unofficial Catalina Patcher from working, so bear in mind that this could turn out to be a time-limited hack.

For more help on installing macOS Catalina on an unsupported machine, or for general macOS Catalina help, make sure to check out our macOS Catalina forum where MacRumors readers are discussing the latest Mac software.

Related Forum: macOS Catalina

Popular Stories

iPhone 17 Pro Blue Feature Tighter Crop

iPhone 17 Pro Launching in Three Months With These 12 New Features

Saturday June 14, 2025 5:45 pm PDT by
The iPhone 17 Pro and iPhone 17 Pro Max are three months away, and there are plenty of rumors about the devices. Below, we recap key changes rumored for the iPhone 17 Pro models as of June 2025:Aluminum frame: iPhone 17 Pro models are rumored to have an aluminum frame, whereas the iPhone 15 Pro and iPhone 16 Pro models have a titanium frame, and the iPhone X through iPhone 14 Pro have a...
iPadOS 26 App Windowing

Apple Explains Why iPads Don't Just Run macOS

Friday June 13, 2025 7:46 am PDT by
iPadOS 26 allows iPads to function much more like Macs, with a new app windowing system, a swipe-down menu bar at the top of the screen, and more. However, Apple has stopped short of allowing iPads to run macOS, and it has now explained why. In an interview this week with Swiss tech journalist Rafael Zeier, Apple's software engineering chief Craig Federighi said that iPadOS 26's new Mac-like ...
Logitech Logo Feature

Logitech Announces Two New Accessories for WWDC

Friday June 13, 2025 7:22 am PDT by
Alongside WWDC this week, Logitech announced notable new accessories for the iPad and Apple Vision Pro. The Logitech Muse is a spatially-tracked stylus developed for use with the Apple Vision Pro. Introduced during the WWDC 2025 keynote address, Muse is intended to support the next generation of spatial computing workflows enabled by visionOS 26. The device incorporates six degrees of...
iphone 16 pro models 1

17 Reasons to Wait for the iPhone 17

Thursday June 12, 2025 8:58 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models simultaneously, which is why we often get rumored features months ahead of launch. The iPhone 17 series is no different, and we already have a good idea of what to expect from Apple's 2025 smartphone lineup. If you skipped the iPhone...
iOS 26 Feature

Apple Seeds Revised iOS 26 Developer Beta to Fix Battery Issue

Friday June 13, 2025 10:15 am PDT by
Apple today provided developers with a revised version of the first iOS 26 beta for testing purposes. The update is only available for the iPhone 15 and iPhone 16 models, so if you're running iOS 26 on an iPhone 14 or earlier, you won't see the revised beta. Registered developers can download the new beta software through the Settings app on each device. The revised beta addresses an...
Mac Studio Feature

Apple Begins Selling Refurbished Mac Studio With M4 Max and M3 Ultra Chips at a Discount

Thursday June 12, 2025 10:14 am PDT by
Apple today added Mac Studio models with M4 Max and M3 Ultra chips to its online certified refurbished store in the United States, Canada, Japan, Singapore, and many European countries, for the first time since they were released in March. As usual for refurbished Macs, prices are discounted by approximately 15% compared to the equivalent new models on Apple's online store. Note that Apple's ...
m4 macbook air pink

Apple Now Selling Refurbished M4 MacBook Air Models

Friday June 13, 2025 3:34 pm PDT by
Apple today added M4 MacBook Air models to its refurbished store in the United States, making the latest MacBook Air devices available at a discounted price for the first time since they launched earlier this year. Both 13-inch and 15-inch MacBook Air models are available, with Apple offering multiple capacities and configurations. The refurbished devices are discounted by approximately 15...