Quick Summary
The "Disk Full" error on macOS indicates that your computer's hard drive or SSD is running out of storage space, preventing you from saving new files, installing applications, or even running existing programs smoothly. This can lead to performance issues and system instability.
Common Causes
- Excessive files and applications: The most common cause is simply accumulating too many files, including documents, photos, videos, and applications, over time.
- Large system files and caches: macOS itself and various applications create temporary files, caches, and system logs that can consume a significant amount of disk space if not managed properly. These can grow unexpectedly.
- Insufficient free space for virtual memory: macOS uses a portion of your hard drive as virtual memory when RAM is insufficient. Lack of free disk space can hinder this, leading to slowdowns.
- Time Machine backups (local snapshots): Time Machine creates local snapshots on your startup disk as temporary backups before moving them to your external drive. If your backup drive is disconnected or unavailable, these local snapshots can accumulate and take up a lot of space.
- Large downloads or installations: Downloads in progress (e.g., operating system updates, large files) can temporarily occupy significant disk space. Failed or incomplete installations can also leave behind large, unused files.
Step-by-Step Fixes
Method 1: Empty the Trash
Step 1: Locate the Trash icon on your Dock.
Step 2: Right-click (or Control-click) on the Trash icon.
Step 3: Select Empty Trash.
Step 4: Confirm the action by clicking Empty Trash in the dialog box.
Method 2: Use macOS Storage Management
Step 1: Click the Apple menu in the top-left corner of your screen.
Step 2: Select About This Mac.
Step 3: Click the Storage tab.
Step 4: Click Manage... This will open the Storage Management window.
Step 5: Review the recommendations provided by macOS, such as Store in iCloud, Optimize Storage, Empty Trash Automatically, and Reduce Clutter.
Step 6: Follow the instructions for each recommendation to free up space. For example, clicking 'Review Files' next to 'Reduce Clutter' will allow you to delete large and unsupported files.
Method 3: Delete Unused Applications
Step 1: Open Finder.
Step 2: Click Applications in the sidebar.
Step 3: Review the list of installed applications and identify those you no longer use or need.
Step 4: Drag the application icon to the Trash, or right-click (or Control-click) on the application icon and select Move to Trash.
Step 5: Remember to Empty the Trash afterward.
Method 4: Remove large, unused files
Step 1: Open Finder.
Step 2: Press Command-F to open a search window.
Step 3: Click the dropdown menu that says 'Kind' and select 'Other'.
Step 4: In the Attributes list, scroll down to and select 'File Size'. Check the box. Now the search window has a 'File Size' option.
Step 5: Click the 'is greater than' dropdown and select an appropriate size like '100 MB'.
Step 6: Review the list of large files and delete any that you no longer need. Be careful not to delete important system files.
Step 7: Remember to Empty the Trash.
Method 5: Disable or adjust Time Machine local snapshots
Step 1: Open Terminal (found in /Applications/Utilities/).
Step 2: To temporarily disable local snapshots, enter the command: sudo tmutil disablelocal and press Return. You'll need to enter your administrator password.
Step 3: To re-enable local snapshots, enter the command: sudo tmutil enablelocal and press Return.
Note: Disabling local snapshots is generally not recommended as it reduces data protection. Consider connecting your Time Machine backup drive more frequently.
Method 6: Clean up system caches and logs
Warning: This method is for advanced users only. Incorrectly deleting system files can cause instability.
Step 1: Use Finder, and press Shift-Command-G to open the 'Go to Folder' dialog.
Step 2: Enter ~/Library/Caches and click Go. Delete the contents of the cache folders within the Caches folder. Do not delete the Caches folder itself.
Step 3: Repeat steps 1 and 2 for /Library/Caches (note the missing '~'). Also repeat for /var/log. You will need to enter your administrator password.
Step 4: Empty the Trash.