Sarah Tew/CNET

MacOS Catalina is here, and with the update comes the transition from 32-bit apps to 64-bit apps. Overall, this is a good thing because it means that apps will run faster and access more memory. The move to exclusively using 64-bit apps in MacOS Catalina has been in the works for years, and Apple has been helping developers transition their 32-bit apps over to the 64-bit format. As part of the transition, Apple last year started requiring all apps in the App Store to use the 64-bit format.

If you regularly update your apps or download them only from the App Store, you'll most likely be fine. But if you're holding onto an old favorite that the developer isn't looking to update -- like Microsoft Office 11 for Mac -- you'll need to decide whether to move to Catalina and lose access to the app, or skip the update and keep using the old software.

While you could take a pass on Catalina, we recommend updating your OS to stay on top of Apple's security patches so you don't risk losing important privacy features.

Before you move to the new MacOS, here's how to check which of your apps won't make the cut to Catalina.

Apple Report All the latest Apple news delivered to your inbox. It's FREE!

Apple

How to check for 32-bit apps on your system



1. Click the Apple icon in the top left corner of your screen.

2. Select About This Mac.

3. Click System Report.

4. Scroll down to the Software section and click Applications.

5. On the right, you'll see a list of apps and a column labeled 64-Bit (Intel). If any of those apps have a No in that column, it means they're not 64-bit apps, so you'll need to update them or find a replacement before you get the MacOS Catalina update.

Need more info? Here's how to check if your Mac will work with Apple's MacOS Catalina update this fall.

Now playing: Watch this: The top 3 upgrades in MacOS Catalina

Originally published earlier this month. Updated to remove an incorrect reference about the number of apps that are incompatible with MacOS Catalina.