What is Other storage on Mac, and how do you reduce it?
Other storage on a Mac is everything macOS could not sort into a named category such as Apps, Documents or Photos. Newer versions of macOS call the same thing System Data. It is mostly caches, app support files, logs, disk images, snapshots and developer files.
You cannot delete Other as a whole, because it is not one thing. You reduce it by finding its largest parts and dealing with each one. This guide shows where to look and what is safe.
Other, System Data and Other Volumes: three different things
The word Other has been used for more than one thing in macOS, which is the source of much of the confusion.
- Other: the label older macOS versions used in the storage bar for files that fit no category.
- System Data: the label current macOS versions use for the same group of files. If you search for Other storage and your Mac shows System Data, you are in the right place.
- Other Volumes: space used by separate volumes that share your disk, such as the recovery system, the volume macOS uses for swap, or a second copy of macOS. This is not your files, and there is normally nothing to clear in it.
How to see it on your version of macOS
On current macOS, open the Apple menu, choose System Settings, then General, then Storage. The grey part of the bar is System Data, and it is also listed as a row at the bottom.
On older versions that still have System Preferences, open the Apple menu, choose About This Mac, click Storage, then click Manage. The bar there is where the Other label appears.
In both cases the number takes a while to settle, and it changes from day to day. That is normal: caches, swap and snapshots grow and shrink as you use the Mac.
What is actually in Other
macOS labels a file by its type and location. Anything that is not an app, a document it recognises, a photo in your library, a message or mail ends up here. In practice that means:
- Caches in ~/Library/Caches and the system cache folders.
- App data in ~/Library/Application Support and ~/Library/Containers that belongs to apps but is not a document.
- Logs, crash reports and diagnostic files.
- Disk images, archives, installers and file types macOS does not recognise.
- Local Time Machine snapshots.
- Swap files and the sleep image.
- Developer files: Xcode build data, simulators, package caches, container images.
- Fonts, plug-ins, extensions and browser data.
Measure before you delete
Because the Storage screen gives you one number and no list, you need another way to see the parts. The command below lists the folders in your Library by size, largest last. It only reads sizes. Most of what macOS calls Other for a typical user is in this list.
Look at the bottom five lines. If Caches is among them, that is the easy part. If Application Support, Containers or Developer leads, the space belongs to particular apps, and the folder names inside tell you which.
du -sh ~/Library/* 2>/dev/null | sort -h | tail -15What is safe to clear
These parts can be removed without losing anything you made. Quit the apps involved first.
- App caches: open ~/Library/Caches and move the contents of the large folders to the Trash. Apps rebuild what they need, so expect slower first launches.
- Logs: the contents of ~/Library/Logs can go to the Trash. You lose history that is only useful when diagnosing a problem.
- Old installers and disk images: .dmg and .pkg files in Downloads for apps you have already installed.
- Leftovers from apps you removed: folders in ~/Library/Application Support named after apps you no longer have. Check the name carefully before deleting.
- Developer build output and package caches, which tools recreate on the next build or install.
What to leave alone
Do not delete swap files, the sleep image or anything under /System or /private/var by hand. macOS owns those, and a restart is the supported way to shrink them.
Do not empty ~/Library/Application Support or ~/Library/Containers as if they were caches. They hold real app data: notes, mail, chat history, game saves, licences. Removing a folder there is the same as erasing that app's data.
Local snapshots normally expire within a day and are released early when the disk runs low. You rarely need to touch them.
Where Diskzy fits
Diskzy has a view called System Data, explained. It breaks the category into named parts, including developer data, caches, app data, logs, swap and sleep image, macOS support files, backups and AI models, each with its size and one of three labels: Safe to clear, Look first or Managed by macOS.
That view is for understanding. Deleting happens in the Clean up tab, where each item is ticked or unticked with a reason, and everything removed goes to the Trash. Diskzy needs macOS 15 or later, so on an older Mac the manual steps above are the way to go.
Common questions
- Is Other storage the same as System Data?
- Yes. Other is the name older macOS versions used for files that fit no category, and current versions call that group System Data.
- Can I delete Other storage on my Mac?
- Not in one step. You can clear parts of it, such as app caches, logs, old installers and leftovers from removed apps. Some parts, such as swap and snapshots, are managed by macOS.
- Why does Other storage keep growing?
- Caches grow as you use apps, logs accumulate, and developer tools download and build files. Swap and snapshots also rise and fall, so the number changes even when you add no files.
- What is Other Volumes in Mac storage?
- It is space used by other volumes that share the same disk, such as the recovery system or a second macOS installation. It is separate from the Other or System Data category.
Related guides
- Caches~/Library/Caches
- Logs~/Library/Logs
- Application Support~/Library/Application Support
- Containers~/Library/Containers
- swapfile/private/var/vm/swapfile0
Uninstall guides
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