How to Clear Cache on a Mac
To clear cache on a Mac or MacBook you empty ~/Library/Caches. That is safe for most apps, because the folder is designed to be disposable. A handful of apps misuse it to store things they can't rebuild, and those are the ones worth knowing about.
Apple's own guidance is that ~/Library/Caches holds data an app can recreate. Delete it and a well-behaved app notices the absence and rebuilds. That is the contract, and the vast majority of apps honour it.
The risk comes from apps that don't.
The fastest way to clear cache on a Mac
- Quit the apps you want to clear. Quit them, not just close the window.
- In Finder choose Go, then Go to Folder, and enter
~/Library/Caches. - Open the folders belonging to the apps you recognise and delete their contents, not the folders.
- Empty the Trash.
The steps are identical on a MacBook Air, MacBook Pro, iMac or Mac mini, since this is macOS behaviour rather than anything hardware specific. Browser caches are usually the largest and are the safest place to start.
The general rule
Quit the app first, delete the contents of its cache folder rather than the folder itself, and expect a slower first launch. That is it. Browsers, media apps, and most productivity software handle this without complaint.
Deleting the folder itself rather than its contents occasionally causes problems, because some apps expect the directory to exist and don't create it. Emptying is safer than removing.
The three exceptions worth knowing
1. Anything currently running
Deleting a cache out from under a running app is the most common way people cause real breakage. The app holds file handles, rewrites partial state, and can end up in an inconsistent condition. Quit first, quit it properly, not just close the window.
2. Mail
Mail's caches and its actual message store live uncomfortably close together. Clearing the wrong thing forces a full re-download of every message on every account, which on a large mailbox takes hours and, on some IMAP servers, causes duplicates. If Mail is misbehaving, rebuilding the mailbox from within Mail is the supported route.
3. Photos
Never touch anything inside the .photoslibrary bundle, including caches. The library is a database, and its thumbnail and analysis caches are referenced by that database. Removing them by hand can corrupt the library and, if iCloud Photos is enabled, propagate the damage.
What about /Library/Caches?
The system-level folder at /Library/Caches (no tilde) is shared across users and includes things macOS itself relies on. There is less to gain here and more to break. The one commonly cited entry, the Adobe and font caches, can be cleared, but the payoff is usually small compared with your user-level caches.
Anything under /System is protected by System Integrity Protection and should stay that way. If a guide tells you to disable SIP to clean caches, stop reading that guide.
How much will you get back?
On a Mac that hasn't been cleaned in a couple of years, user caches typically hold 5–15 GB. Browsers are usually the top three entries. Design tools, video editors and IDEs can each hold far more.
Worth being clear about the benefit: this reclaims space. It doesn't make your Mac faster, and it briefly makes it slightly slower while caches rebuild. If you aren't short of space, there's little reason to do it at all.
Clear caches without the guesswork
CleanMachine targets specific known-safe cache paths rather than wiping whole directories, skips the ones that hold real state, and moves everything to a recoverable Trash first. Free to scan.
↓ Download Free & ScanIf something does break
Most cache-related breakage is fixed by restarting the app, then restarting the Mac. Preferences that get lost are stored separately in ~/Library/Preferences, if an app forgot its settings, you deleted more than caches.
This is the reason to move files to the Trash instead of deleting them permanently. A recoverable mistake isn't really a mistake.