What is safe to delete on a Mac, in one list
A verdict on every category, from definitely safe to never touch, with the reason for each and where to read more.
Most cleanup advice tells you where space is. The harder question is which of it you can remove without consequence, and the answer is genuinely different per category. This is the whole list, sorted by how safe each one is.
Definitely safe
| What | Why | More |
|---|---|---|
| The Trash, including on external drives | You already decided | Trash will not empty |
| Installers and disk images in Downloads | The app is installed | Downloads |
| Build output and dependency folders | Rebuilt by a build | node_modules |
| Package manager caches | Redownloaded | npm cache |
| Browser caches | Rebuilt as you browse | Chrome |
| Logs and crash reports | Diagnostics only | System logs |
| Old device firmware files | Redownloaded, and expire anyway | IPSW files |
Safe with one check first
- Old device backups. Safe once the device has a newer backup. iPhone backups
- Simulator runtimes and Xcode caches. Safe unless you need that iOS version today.
- Docker images and build cache. Safe. Volumes are not, and that is a different command.
- Old user accounts. Safe after checking what is inside. Old accounts
- Virtual machines you no longer boot. Safe if nothing inside them is the only copy.
Not safe without understanding what it is
| What | Risk |
|---|---|
Anything in Application Support | App data and cache sit side by side |
Containers and Group Containers | Can hold the only copy of your notes or messages |
Preferences | You lose settings and licences |
| Mail and Messages folders | Local history, sometimes the only copy |
| A Photos library or its contents | The database and the images are one thing |
| Anything inside a project you did not create | Lock files and state files matter |
Never
- The system volume, which is sealed and read only anyway.
/System/Libraryand/Librarysystem components.- Anything in
/private/var/vm, which macOS recreates and needs. - Time Machine backup folders, which must be removed with tmutil.
- A file you cannot identify, in a folder you cannot identify. Look first.
The rule that covers everything not listed
If it can be downloaded again, built again or synced again, it is safe. If it exists only on this Mac, it is not. Almost every mistake in this category comes from assuming a folder is the first kind when it is the second.
Common questions
What is always safe to delete on a Mac?
The Trash, installers in Downloads, build output and dependency folders, package manager caches, browser caches, logs and old device firmware files. All are either already discarded or regenerated.
What should I never delete on a Mac?
System files, anything in /private/var/vm, Time Machine backup folders and any file you cannot identify. The system volume is sealed and read only, so most of it cannot be removed anyway.
Is it safe to delete files in Application Support?
Not as a category. That folder mixes disposable caches with the only copy of some apps' data, so each folder needs checking individually before removal.
What is the general rule for safe deletion?
If it can be downloaded, rebuilt or synced again, it is safe. If it exists only on this Mac, it is not. Deleting through something that uses the Trash makes mistakes recoverable either way.