How to check for 32-bit apps (macOS)

  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 in the left sidebar and select Legacy Software in the sidebar. All legacy software is 32-bit.
  5. If you don’t see Legacy Software in the sidebar, select Applications in the sidebar, then check the list of apps on the right. The column labeled “64-Bit (Intel)” shows “No” for apps that are 32-bit.

high sierra system report apps 64 bit

You’ll need to update 32-bit apps or find a replacement before you upgrade to macOS Catalina (10.15) or above.

When upgrading to macOS Catalina, the installer shows a list of recently used apps that are 32-bit. You can review this list before choosing whether to cancel or continue the installation:

Catalina installer window showing list of 32-bit apps

macOS Catalina also shows a prohibitory symbol  over the icon of each 32-bit app in the Finder, letting you know that the app will not open.