Matt Gemmell tweeted:

Do like the new macOS Sierra thing where you can find which apps/docs/etc you’ve not used in a while.

Embedded in the tweet was an image, showing his Mac after he launched About This Mac and tapped the Storage tab. Like so:

• Choose “About This Mac” from your Mac’s Apple menu.
• Tap the Storage tab
• Tap the Manage… button

Lots of things you can do here. For starters, you can tap Applications (in the sidebar), then tap the Last Accessed header to list Applications in reverse order, which will show you the apps you haven’t accessed in a long time. The longest neglected app I found on my Mac was iPod Software 2.1 Updater.app, which I haven’t touched since 2003.

Before you start deleting old stuff, you might read through the responses to Matt’s tweet, especially the cautions from Kirk McElhearn about deleting Microsoft Office related apps.

And, of course, be sure you back up your Mac before you even think about deleting anything.