Mac storage full – what should you do?
How do I check what's using storage on my Mac?
Go to System Settings › General › Storage. A colored bar shows how much space Applications, Documents, Photos, System Data and other categories use; the numbers often take a moment to calculate.
Click the info button (ⓘ) next to a category to see details and remove items right there. On macOS 12 and earlier, the same view lives under Apple menu › About This Mac › Storage.
What do the storage categories mean?
The categories group files by type and origin. They're macOS's own estimate, so the lines between them aren't always sharp.
- Applications: installed apps, including big ones like Xcode or games.
- Documents: files in your home folder, such as downloads, videos and archives.
- Photos: your Photos library – often the single largest item.
- iOS Files: local backups and software updates for iPhone and iPad.
- macOS: the operating system itself; protected and can't be shrunk.
- System Data: caches, logs, local snapshots and anything that doesn't fit another category.
Which quick fixes free up the most space?
You'll usually gain the most from a few big files, not from lots of small ones. Work through this list from top to bottom:
- Empty the Trash: deleted files keep taking up space until you choose Finder › Empty Trash.
- Clean out Downloads: remove old installers (.dmg, .pkg), archives and duplicate files.
- Move large videos: put movies and screen recordings on an external drive.
- Delete old iPhone and iPad backups: via the connected device in Finder or under Storage › iOS Files.
- Use iCloud: with Optimize Mac Storage (in your iCloud settings under your name), macOS offloads rarely used iCloud Drive files.
- Messages attachments: delete large attachments under Storage › Messages, or pick a shorter period in Messages under Settings › General › Keep messages.
Why does macOS need free space?
macOS needs free space to stay stable and responsive. When memory runs low, the system writes data to swap files on the SSD – without room for them, apps slow down or quit.
System updates also need far more space to unpack and install than their download size suggests. Keep a generous buffer instead of filling the drive to the last gigabyte.
What's safe to delete – and what isn't?
Your own files that you recognize and no longer need are safe, as are installers and archives whose contents are already installed or extracted.
Stay away from system folders like /System, /Library and /private, and from unfamiliar folders in ~/Library: they hold settings, databases and app data that programs need to work. Move things to the Trash rather than deleting them permanently, so you can undo a mistake.
Free up Mac storage in 6 steps
Open the storage overview
Open System Settings › General › Storage and wait for the calculation to finish.
Review and empty the Trash
Check what's in the Trash, then choose Finder › Empty Trash.
Clean up Downloads
Sort your Downloads folder by size in Finder and remove old installers, archives and duplicates.
Move large videos
Copy large videos to an external drive and make sure they open there before deleting the originals.
Remove old device backups
Connect your iPhone or iPad, select it in the Finder sidebar, and delete backups you no longer need under General › Manage Backups.
Find the remaining large folders
Scan your startup disk with a disk analyzer such as DiskDonut to spot any large folders that are left.
Frequently asked questions
Why is my Mac storage full when I barely have any files?
Large items often hide in places you don't see every day: the Photos library, iPhone backups, Messages attachments, or System Data such as local snapshots. The storage overview in System Settings and a disk analyzer show where the space actually goes.
Is emptying the Trash enough?
It's a good first step, because deleted files keep using space until the Trash is emptied. Photos also has its own Recently Deleted album, which only clears itself automatically after up to 30 days.
Is iCloud's Optimize Mac Storage safe?
Yes, your files stay in iCloud Drive. When space runs low, macOS only removes the local copies of rarely used files and downloads them again when you open them – but they aren't available offline.
Can I just delete the caches in ~/Library/Caches?
Many caches get rebuilt, so deleting them often frees space only temporarily and can disrupt running apps. Don't delete unfamiliar folders in ~/Library; use the app's own cleanup options or a tool that classifies every item.