How to find out if your Mac’s software is 32- or 64-bit

MacOS 10.14 Mojave, the version of the Mac operating system before the new macOS Catalina, is the last version that supports 32-bit software. With Catalina, only 64-bit software will be supported.

Catalina is here and if you decide to upgrade to the new macOS, you need to do a bit more than usual to prepare your Mac. You need to make sure your apps are 64-bit versions. If your app is a 32-bit version, it will not work.

macos mojave 32 bit app alert Apple

Apple actually started to warn people about the change with macOS 10.13 High Sierra. If you launch a 32-bit app in High Sierra, an alert pops up to tell you that your app needs to be updated. The alert appears only once in High Sierra, and in Mojave, it appears every 30 days.

If you can’t recall whether an app needs to be upgraded or not, there are a couple of ways to find out besides the launch alert. Here’s how.

Use Go64 to find 32-bit apps on your Mac

St. Claire Software has a teriffic app called Go64 (free, donations accepted) that scans the software on your Mac and tells you whether the each app is 64-bit or not. Go64 is fast and it also provides web links to the app developer’s website, so you can go see if the developer has an update. Learn more about Go64.

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Go64 provides a more detailed look at which apps need updated or deleted before installing macOS Catalina.

Find 32-bit apps on your Mac through System Report

1. In the Finder, click on the Apple menu and select About This Mac.

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2. In the Overview section, click on the System Report button.

3. In the left column of the System Report, scroll down to the Software section. Then select Applications.