How to check and free up storage on a Mac

2 min read · 5 steps · Updated 2 October 2026

A Mac with a nearly full disk gets slow and cannot install updates. The Storage page shows where the space has gone and has tools to get it back.

These steps are for recent versions of macOS, where the settings app is called System Settings. The pictures are simplified diagrams, not screenshots.

Step by step

1. Open System Settings

   Click the Apple menu in the top left corner of the screen and choose System Settings.

   Done

2. Click General, then Storage

   General is in the list on the left. Storage is on the right.

   Done

3. Read the bar

   Wait a few seconds while the Mac calculates. The coloured bar shows Applications, Documents, Photos, System Data and more, and the free space on the right.

   Done

4. Use the recommendations

   Empty Bin Automatically deletes items that have been in the Bin for 30 days. Optimise Storage removes films and TV programmes you have already watched. Store in iCloud moves files online, which needs enough iCloud space.

   Done

5. Delete large files

   Click the i button next to Documents. The Large Files tab lists the biggest files on the Mac. Select what you no longer need and click Delete. Do the same under Applications for apps you do not use.

   Done

Good to know

Empty the Bin when you finish, or the space does not come back: right-click the Bin in the Dock and choose Empty Bin.

The Downloads folder is often the largest forgotten folder. Open it in Finder and sort by size.

System Data is managed by macOS and shrinks by itself over time. Restarting the Mac often reduces it.

In short: System Settings, General, Storage. Turn on the recommendations, then delete large files and unused apps.