Clean-up · free up space
How to clean up a Mac
Back up first. Then clear Downloads and the Desktop, find large and duplicate files, uninstall the apps you no longer open, empty the caches, trim login items and empty the Trash. Do your own files by hand, and let anything regenerable go without a second thought.
A clean-up is two different jobs. Your own files need you to decide what goes; caches and leftovers only need checking that they are what they look like. This list does the first kind early, while you have the patience, and the second kind after.
1. Back up
Plug in the Time Machine drive and let it finish, or check iCloud has caught up. Everything below is reversible until you empty the Trash; a backup makes it reversible afterwards too.
2. Downloads
Open Downloads, switch to list view and sort by size. Installers (.dmg, .pkg) for apps you have already installed can go. So can archives you have already unpacked. This folder is usually the quickest gigabyte on the Mac.
3. The Desktop
Screenshots pile up here. Move what you want to keep into Documents or Pictures and delete the rest. A tidy Desktop is not faster in itself, but a Desktop with thousands of files does make Finder slower to redraw.
4. Large files
System Settings → General → Storage → Documents opens a list of large files sorted by size. Old videos, disk images and exports are typical. Anything you want to keep but rarely open is a candidate for an external drive rather than the Trash.
5. Duplicates
The same file saved twice — a download repeated, an export kept in two folders, a photo re-saved at another size. Finder cannot find them for you; a duplicate finder can. Always keep one copy, and check which copy other things point to before deleting it.
6. Apps you no longer use
Storage settings → Applications sorts your apps by size. Remove the ones you have not opened in months, and remove what they left behind with them — see how to uninstall apps on a Mac.
7. Caches
Quit your apps, then empty ~/Library/Caches and the hidden ~/.cache. Everything in them regenerates, so this is the one step that needs no deciding. Caches are one of the largest parts of System Data in Storage settings. The full steps are on how to clear the cache; if you write code, add Xcode DerivedData and old simulator runtimes.
8. Login items
System Settings → General → Login Items & Extensions. Remove the apps that do not need to open the moment you log in. This is the clean-up step that helps speed rather than space; the others are on how to speed up a Mac.
9. Empty the Trash and restart
Nothing above frees a byte until the Trash is emptied. Then restart, which clears macOS's own temporary files and lets it release swap.
How often
Your own files: when the disk tells you to. Caches: they grow back, so clearing them on a schedule when free space runs low beats a big clean twice a year. If the disk is already nearly full, skip ahead to Mac storage full, which puts the fastest steps first.
Where the app comes in
RefreshYourMac has a category for most of this list: Downloads Folder, Large Files, Duplicate Files, Duplicate Pictures, Unused Applications, the caches, and the Trash. It measures all of them for free, rates each one with a safety level, and deletes nothing without asking. Large files can go to another drive instead of the Trash, and the safe categories can be cleared on a schedule.