How to clear the cache on a Mac, and when it isn't worth it
What's in ~/Library/Caches, what happens when you delete it, how to clear one app's cache safely, and why wiping everything buys less than you'd think.
On this page
Caches are files apps keep so they don't have to download or rebuild the same thing twice: thumbnails, web pages, downloaded updates, compiled code. Deleting them is safe in the sense that apps recreate them. It's pointless in the sense that they grow back, usually within days.
So the useful move isn't wiping the whole cache folder every month. It's finding the one app whose cache has grown out of proportion, or is broken, and clearing just that one.
What's actually in there
Your caches live in ~/Library/Caches. On my Mac that folder holds 4.4 GB across 187 subfolders, and the top four account for most of it:
| Folder | Size | What it is |
|---|---|---|
One app's org.sparkle-project.Sparkle folder | 1.4 GB | An update that app had downloaded two days earlier |
Google | 1.0 GB | Chrome's browser cache |
A folder ending in .ShipIt | 881 MB | Another app's update, downloaded that afternoon |
org.swift.swiftpm | 667 MB | Swift Package Manager's copies of package repositories and binaries |
Two of the four biggest weren't really caches at all. They were app updaters holding on to updates they had downloaded. Everything else was small, which is typical: caches follow the same pattern as the rest of the disk, a few big folders and a long tail of tiny ones. To see your own top ten, largest last:
du -sh ~/Library/Caches/* 2>/dev/null | sort -h | tail -10Most folder names are an app's bundle identifier, like com.company.appname, so you can usually tell whose they are.
When clearing a cache actually helps
- One cache has grown far beyond what makes sense. Music and video apps with offline downloads, chat apps that cache every image anyone ever sent, and package managers are the usual culprits.
- An app is misbehaving in a way its developer blames on a corrupted cache: wrong thumbnails, stale web content, a login loop.
- You've uninstalled an app and its cache stayed behind. Nothing will ever clean that up for you.
When it doesn't
As routine maintenance. Clearing every cache gets you a few gigabytes for a few days, and in exchange every app is slower the first time it opens while it rebuilds what you deleted. It won't make your Mac faster either. If anything, the next hour is slower.
I'd also be wary of any tool that recommends clearing caches as a weekly habit and shows a big number when you do. That number comes back.
How to clear one app's cache safely
- Quit the app. Deleting a cache out from under a running app is how you get the corruption you were trying to fix.
- In Finder, choose Go → Go to Folder… (Shift-Command-G) and enter
~/Library/Caches. - Find the folder for that app and move it to the Trash.
- Open the app and check it behaves. Then empty the Trash.
Moving the folder to the Trash instead of deleting it outright gives you an undo if the app turns out to have kept something important in there. It happens occasionally, and it's the developer's fault when it does, but it's still your afternoon.
Developer tool caches: use the tool's own command
Package managers know which parts of their cache are safe to drop, so let them do it:
brew cleanup # Homebrew: old versions and old downloads
npm cache clean --force # npm: the whole cache in ~/.npm
pip cache purge # pipFor Swift Package Manager, quit Xcode and delete ~/Library/Caches/org.swift.swiftpm; packages are fetched again on the next build. Xcode itself has bigger folders than any of these, covered in where Xcode's disk space goes.
Browser caches: use the browser
Browsers keep their cache in one place and your profile (history, saved passwords, extensions, open tabs) somewhere else. Deleting folders by hand is how people lose the second while trying to clear the first. Each browser has a proper option:
- Safari: turn on Settings → Advanced → "Show features for web developers", then choose Develop → Empty Caches (Option-Command-E).
- Chrome: press Shift-Command-Delete and choose "Cached images and files".
- Firefox: Settings → Privacy & Security → Cookies and Site Data → Clear Data…, and leave only the cached files option ticked.
On macOS 27 there's another reason to leave profile folders alone: several browsers' folders in ~/Library/Application Support are now protected from other apps. More on that change.
Caches to leave alone
/System/Library/Caches: part of the sealed system. macOS manages it./Library/Caches: shared by all users and usually tiny. It's 5.9 MB on my Mac; not worth an admin password./private/var/folders: per-user temporary files and caches that macOS manages. A restart clears some of it. Deleting things there while you're logged in can break running apps.- Caches of apps that are open right now.
What Spaceback does with caches
Spaceback's Junk scan lists app caches, Chrome's and Firefox's caches and app logs, each with its real size, and you choose what goes. What you choose moves to the Trash, not straight into oblivion. That part is free. Spaceback never offers Mail, Messages, Safari or Photos data for cleaning, by design. If you turn on scheduled scans, they only find things; nothing leaves until you've reviewed it.
Vlada Misici builds Spaceback, a storage cleaner for Mac and iPhone. Every number in these posts was measured on a real Mac, and every command was run before it went on the page. Found a mistake? Email vlada@queazy.app and it gets fixed.