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How to free up storage on Mac (a real, ordered checklist)

A blunt, in-order checklist for freeing up storage on a Mac. Start at the top, stop when you've got the space you need.

4 min read

Most “free up storage on Mac” guides list 40 things in random order. You don’t need 40 things. You need the few that recover the most space for the least risk, ordered so you can stop the moment the warning goes away.

The checklist

Each step is ordered by likely payoff per minute spent.

  1. Empty your Downloads folder of installers. Filter Downloads by .dmg, .pkg, and .zip. None of these need to stay.
  2. Delete old iOS backups. Finder > your iPhone > Manage Backups. If you have a backup from a phone you don't own anymore, delete it.
  3. Clear Mail attachments. Mail > Settings > Accounts > Advanced. Set "Download Attachments" to "Recent" or "None." Existing cached attachments live in ~/Library/Containers/com.apple.mail/Data/Library/Mail Downloads/.
  4. Trash old video and project files. Run find ~ -type f -size +500M 2>/dev/null | sort in Terminal. Look for old screen recordings, Final Cut events, and abandoned exports.
  5. Turn on "Optimize Mac Storage" for iCloud Photos. Photos > Settings > iCloud. macOS will keep only thumbnails locally and pull originals on demand.
  6. Drop leftover app data. Uninstalled apps leave caches in ~/Library/Application Support and ~/Library/Caches. Sort by size and delete folders for apps you no longer have.
  7. Empty the Trash. Right-click the Dock Trash icon, check the size, and empty it.
  8. Hunt duplicates. The last big bucket. Easy to do wrong by hand.

Useful Terminal commands

To see where your space is actually going:

du -sh ~/Library/* 2>/dev/null | sort -h | tail -20

That prints the 20 largest folders inside ~/Library, which is where invisible space hides on macOS.

For the home folder as a whole:

du -sh ~/* 2>/dev/null | sort -h

On duplicates

After you’ve worked through 1–7, what’s left is usually duplicates and the parts of macOS you shouldn’t touch. Duplicates are particularly worth hunting because each copy looks legitimate in Finder — there’s no visual cue that it’s a second instance of a file you already have.

You can do it manually by sorting by size and name (slow, error-prone), or you can Download Dupe and let it hash every file with SHA-256 to find byte-identical matches. Dupe is $14.99 once, moves files to the Trash instead of deleting them, and won’t touch system files or application bundles. It’s the only step on this list I’d recommend a tool for.

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