“Your disk is almost full”: what to do first

What’s using the space?

Storage in System Settings shows how much of your disk is used, and what’s using it.

1. Choose Apple menu > System Settings, then click General in the sidebar. You may need to scroll down.
2. Click Storage. Wait a moment while macOS adds up each category.
3. Read the bar at the top: it shows used and available space. Below it, the categories are listed by size.

Categories such as Documents and Applications open with the info button (ⓘ), so you can manage their files. System Data is different: macOS manages it, and you can’t delete it directly. What is System Data on a Mac? explains it.

Step 1: Empty the Trash

Files you move to the Trash stay on your disk until you empty it. It’s the quickest space to get back.

1. Click the Trash in the Dock.
2. Look through it once, in case something there is still needed.
3. Click Empty in the upper-right corner of the window, or choose Finder > Empty Trash, then confirm.

Emptying the Trash deletes those files for good, so check it first.

Step 2: Delete large files and old downloads

A few big files often take more space than everything else together. Storage lists them:

1. In Storage, click the info button (ⓘ) next to Documents.
2. Click Large Files, then click Size to sort, biggest first.
3. Select a file you don’t need and click Delete, or click Show in Finder to look at it first.

Click Downloads in the same view, or choose Go > Downloads in Finder. Installers you’ve already used, such as disk images (.dmg), are usually safe to delete. How to find large files on a Mac, safely goes further.

Step 3: Move files you want to keep to an external drive

Files you still need, such as finished projects and photo or video libraries, can live on another drive.

1. Connect the external drive to your Mac.
2. Open a Finder window and select the files you want to move.
3. Drag them to the drive, listed below Locations in the Finder sidebar.
4. When the files are on the drive, open one or two there to check them. Then delete the originals from your Mac and empty the Trash.
5. Before you unplug the drive, click the Eject button next to its name in the sidebar.

On this Mac, emptying the 6.88 GB Trash and moving the 11.8 GB drone video takes free space from 89.52 GB to 108.20 GB.

Step 4: Let Storage keep space free

At the top of Storage, three recommendations keep space free from then on:

• Store in iCloud: keeps files from your Desktop and Documents folders in iCloud Drive, and only recent files on your Mac when space is needed. It uses your iCloud storage plan.
• Optimize Storage: removes Apple TV movies and shows you’ve already watched, and keeps only recent email attachments on your Mac when space is low.
• Empty Trash automatically: erases items that have been in the Trash for more than 30 days.

macOS also clears caches and logs that are safe to delete when space is needed, such as interrupted downloads and staged updates.

Still not enough room for a macOS update?

Starting up in safe mode clears some system caches, which macOS creates again as needed. Apple says this can free enough space for a task such as installing a macOS update.

• Mac with Apple silicon: shut down. Press and hold the power button until you see “Loading startup options”. Select your startup disk, then hold Shift and click Continue in Safe Mode.
• Intel-based Mac: turn on or restart your Mac, then hold Shift until you see the login window.

To leave safe mode, choose Apple menu > Restart.

Questions people also ask

Why is my Mac still full after deleting files?

Files you delete go to the Trash, and they take up space until you empty it. Empty the Trash, then check Storage again.

Does buying more iCloud storage fix a full Mac?

Not by itself. An iCloud plan is space in iCloud, not on your Mac. Turning on Store in iCloud is what moves files there, keeping recent ones on your Mac when space is needed.

Can I delete System Data?

No. macOS manages System Data, so there’s nothing in it to select. Empty the Trash and delete your own large files instead.

How much free space should I keep?

Apple doesn’t give a single number. Keep enough for macOS updates and for your largest regular job. How much free space should a Mac have? explains why.