In short
- Browser caches are safe to clear. Bookmarks, passwords and history are stored elsewhere.
- Most app caches rebuild themselves. A few hold downloads, such as offline music in Spotify, so check those first.
- Don't delete the whole
~/Library/Cachesfolder, or anything in~/Library/Application Support: that is data, not cache. - Clearing a cache frees disk space. It doesn't make a Mac faster.
What a cache is
A cache is a copy an app keeps so it doesn't have to fetch or work out the same thing twice: the images on a web page, a package it downloaded, a file it built. The app can get all of it again, which is why caches are the first place to look when a disk is full.
Caches are also a large part of what macOS reports as System Data.
Which caches are safe to delete
- Browser cachesBrowsers download them again as you browse. Bookmarks, passwords and history are stored elsewhere.Safe to delete
- Other app cachesMost rebuild, but a few hold downloads you'd miss, such as offline music.Check first
- Temporary files macOS managesmacOS clears these itself.Keep
Don't delete a folder because it is large. ~/Library/Application Support and ~/Library/Containers sit next to Caches, and they hold app data: message history, settings and licenses. That is not cache, and it doesn't come back.
How to clear your browser's cache
- Safari. Choose Safari → Settings, then click Privacy. Click Manage Website Data, then Remove All. This removes cookies too, so websites will ask you to sign in again (Apple's steps).
- Chrome. At the top right, select More, then Delete browsing data. Choose a time range, tick Cached images and files, and select Delete data. Leave cookies unticked to stay signed in (Google's steps).
- Firefox. Open Settings → Privacy & Security and use the Clear Data button under Cookies and Site Data, with the cache option ticked.
How to clear an app's cache by hand
- Quit the app. An app that is open is still writing to its cache.
- Open the Caches folder. In Finder, choose Go → Go to Folder and enter
~/Library/Caches. - Open the folder named after the app. Many are named like
com.company.app. Move what is inside it to the Trash, not the folder itself. - Empty the Trash. The space comes back when the Trash is emptied.
Caches that are not worth deleting
- Caches that hold downloads. Spotify keeps offline music in its cache. Testing tools keep whole browsers in theirs, and AI tools keep models, which take a long time to download again.
- System caches.
/Library/Cachesand the private cache folders under/private/var/foldersbelong to macOS and to every account on the Mac. Leave them to macOS. - Anything an open app is using. Quit the app first, or it rewrites the files as you remove them.
How StorageJanitor handles caches
StorageJanitor marks a cache Safe to delete only when it knows what is inside: the browser caches above, known developer caches, and the cache folders inside apps such as Slack and Discord. Every other cache is Check first, so it is moved to the Trash, not deleted.
Before anything is removed you see the exact list, with each item's name, path and size. If it can see that the app owning a cache is open, that cache is skipped until you quit the app.
Questions people ask
Is it safe to delete everything in ~/Library/Caches?
Mostly, but not entirely. Most apps rebuild their cache, but a few keep downloads there, such as offline music in Spotify. Clear the folder of one app at a time, with that app closed, and don't delete the Caches folder itself.
Does clearing the cache delete my passwords or bookmarks?
No. A browser stores bookmarks, passwords and history separately from its cache. Removing cookies and website data is a different step, and that one signs you out of websites.
Does clearing the cache make a Mac faster?
No. It gives disk space back. Apps then rebuild what they need, so the first launch or page load afterwards can be slower.
Why does the cache come back after I clear it?
Because apps rebuild it as you use them. A cache that returns is doing its job; it only needs clearing when you need the space or an app is misbehaving.
How do I clear the system cache on a Mac?
You don't need to: macOS manages its own caches. Restarting clears temporary files, and Apple says starting in safe mode clears certain system caches. See Apple's guide to freeing up storage.