macOS Catalina was the newest operating system by Apple until macOS Big Sur succeeded it in 2020. If your Mac still runs Mojave or an even older macOS version, you'll be amazed by all the new features and improvements in Catalina. So here’s how to upgrade to macOS Catalina.

First, clear out the junk

How to upgrade your Mac to the new Apple macOS (Mojave, Catalina). Download CleanMyMac X free edition here: update your macOS to lat.

When you do a regular upgrade, the installer replaces some files on your Mac with others, but leaves most untouched. That means that all the system junk your Mac has accumulated over the years stays there. And as you upgrade year after year, you accumulate more and more. As you can imagine, upgrading your operating system on a junk-filled Mac is rather like putting one layer of wallpaper on top of another — eventually you have to scrape it off and start again.

• This usually occurs on machines that support High Sierra (macOS 10.13) natively, but whose owners have not installed High Sierra on them previously. Installing High Sierra on these machines will update the machine's system firmware, allowing it to boot from an APFS volume. This is necessary in order to boot Catalina.
• Guide: Update Directly to macOS Catalina. Update your existing Clover install to version r4910 or higher using MultiBeast or official Clover package. Open Clover configuration folder on the root of your system drive or EFI Partition using EFI Mounter v3.

Likewise, it’s always a good idea to clear out the clutter before you upgrade. My recommendation, after years of experience upgrading Macs, is that you use CleanMyMac X. It’s very quick and easy to use and will get rid of clutter, making your Mac run more smoothly and freeing up tens of gigabytes of disk space. You can either let it decide what to remove or go through its scan results yourself and decide what to trash and what to keep.

Then, backup your Mac

As you will see below, there are a couple of different ways you can upgrade to Catalina, but before you decide, and certainly before you upgrade, you should make a full backup of your current Mac setup. Upgrading one OS on top of another carries very few risks, but they are not non-existent so be safe now rather than sorry later. If you use Time Machine you can make a backup with that. But the best idea is to make a complete bootable clone of your current startup disk on an external drive.

To clean install or not to clean install

Remember I said you had a couple of options for upgrading? Here they are:

1. Regular install
2. Clean install

A regular install places Catalina files on your startup disk over the top of whatever OS you’re currently running. It doesn’t overwrite anything else. So all your applications, documents, settings, photos, movies, and music stay where they are. Unfortunately, all the junk files your Mac has accumulated also remain there. This option is quicker in the short-term, but your Mac won’t run as smoothly in the long-term. If you choose this option, I’d definitely recommend you use CleanMyMac X to clear out the clutter, before you upgrade.

A clean install erases your startup disk completely and then installs macOS Catalina on a completely clean disk. It takes longer, but in the long run your Mac will run more quickly and more smoothly. You will have to clone your startup disk before you start, and then spend time reinstalling applications and setting them up afterwards, however.

How to do a regular install of macOS Catalina

1. Check that your Mac can run Catalina. Here’s the list of compatible Macs:

MacBook 2015 and later

MacBook Air 2012 and later

MacBook Pro 2012 and later

IMac 2012 and later

IMac Pro 2017 and later

Mac Pro 2013 and later

2. Make sure you’re connected to the internet and have a reliable connection. If you’re using a MacBook, MacBook Air, or MacBook Pro, plug it into mains power.

3. Launch the App Store app on your Mac and search for 'macOS Catalina.'

4. When you find it, click 'Get.'

5. Wait for Catalina to download and when it’s ready to install, click Continue. Type in your admin username and password, if necessary.

Can You Update Macos High Sierra To Catalina

6. Wait for Catalina to install. Your Mac will restart several times and it may take a while, so be patient! If you are using a laptop, don’t close the lid.

7. Once it has finished installing, you can continue to use your Mac as normal.

How to clean install macOS Catalina

We have covered clean installing Catalina in more detail in this article How to Clean Install macOS Catalina but here’s a summary.

1. Make a full bootable clone of your Mac, just in case the worst happens.
2. Grab a USB stick that’s at least 16GB capacity, or an external hard drive or USB stick.
3. Erase and re-format the USB stick or external disk.
4. Create a bootable installer on the disk.
5. Boot from the new install disk and use Disk Utility in macOS Utilities to erase your startup disk.
6. Go back to macOS Utilities and choose install macOS, with your startup disk as the location for the install.

Once it’s finished, set up your Mac, reinstall applications and restore your settings.

My apps are slow or stopped working on macOS Catalina

Okay, you’ve successfully installed macOS 10.15 Catalina. But some of your apps are no longer available. That’s a heavy blow from macOS Catalina as it no longer supports 32-bit apps. According to Apple, 64-bit apps are more memory-efficient than 32-bit ones. But for most of us it means we will lose many favorite games and applications, including Photoshop CS. To minimize the damage, you should first check how many 32-bit apps you have. It's possible to do with the same Mac maintenance app we've mentioned above.

• Run CleanMyMac X — you can download a free edition here.
• Click the Uninstaller tab.
• Now, by clicking on the 32-bit tab, you will see the list of 32-bit apps on your Mac.

Next up, click the Updater tab.
Here you can update your 32-apps (and all the rest of apps) to newer versions. Many developers have already optimized their software for 64-bit architecture. With this method you’ll update all your software in one-go to make it Catalina-friendly. As you can see, I can update 17 apps with just one button.

Thanks for reading this article. Hope you will like it on Catalina!

To get the latest features and maintain the security, stability, compatibility, and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.

Learn how to upgrade to macOS Big Sur, the latest version of macOS.

Check compatibility

The version of macOS that came with your Mac is the earliest version it can use. For example, if your Mac came with macOS Big Sur, it will not accept installation of macOS Catalina or earlier.

If a macOS can't be used on your Mac, the App Store or installer will let you know. For example, it might say that it's not compatible with this device or is too old to be opened on this version of macOS. To confirm compatibility before downloading, check the minimum hardware requirements:

• macOS Catalina 10.15 hardware requirements
• macOS Mojave 10.14 hardware requirements
• macOS High Sierra 10.13 hardware requirements
• macOS Sierra 10.12 hardware requirements
• OS X El Capitan 10.11 hardware requirements
• OS X Yosemite 10.10 hardware requirements

Mac Os Update High Sierra To Catalina

Download macOS using Safari on your Mac

Mac Os High Sierra Update To Catalina

Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.

• macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite, Mavericks
• macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion
• macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion

Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.

Should You Upgrade From High Sierra To Catalina

• macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion, or Lion
• OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion, or Snow Leopard
• OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion, or Snow Leopard