How to Find What's Taking Up Space on Your Mac

Start with Storage settings

macOS groups your storage into categories and shows them as a coloured bar. This is the quickest way to see whether the problem is apps, documents, photos, mail or something else.

1. On macOS 13 Ventura and later: Apple menu > System Settings > General > Storage.
2. On macOS 12 Monterey: Apple menu > About This Mac > Storage, then Manage.
3. Wait for every category to finish calculating; the numbers keep changing until then.
4. Hover over the bar to see each category's size, then click the Info button (i) next to a category in the list to see what is inside it.

Inside a category you can sort items, select one and click Show in Finder to see where it is stored. For Documents, there are views for large files and downloads, sorted by size or by when they were last opened.

What the storage categories mean

Which categories appear depends on your Mac and what you use. Other Users & Shared shows how much the other accounts on the Mac use, but you can't delete their files from your account.

Why System Data is so large

System Data is the category people ask about most. Apple describes it as logs, caches and virtual memory files, plus Apple and third-party files that don't fit a more specific category, and notes that it can't be managed directly from Storage settings.

In practice it can include app caches, developer tool data, virtual machine images and container disk images. To see what is really in it, look at folder sizes in your home folder and Library, as described below. The data usually belongs to a specific app, and that app is the right place to clean it up.

Free space and available space are not the same thing. Available space also counts purgeable files that macOS can remove when it needs room, so it can be noticeably larger than free space.

Check folder sizes in Finder

Storage settings tells you which category is large; Finder tells you which folder.

1. Open a Finder window and go to your home folder (Go > Home, or Shift-Command-H).
2. Select a folder and choose File > Get Info (Command-I) to see its size. To see the total of several folders at once, select them, hold Control and choose File > Get Summary Info.
3. In list view (View > as List), click the Size column header to sort by size. Choose View > Show View Options (Command-J) to change which columns list view shows.
4. Turn on View > Show Status Bar to see how much space is available on the disk at the bottom of the window.

Large folders to check first are Downloads, Movies, Desktop, Documents, and the hidden Library folder (in Finder, choose Go and hold Option to show it).

Get an exact list with Terminal

Finder can be slow to total big folders. The du command in Terminal measures folders directly and only reads the disk.

du -h -d 1 ~ | sort -h

• du reports the space each folder uses on disk.
• -h prints sizes as K, M and G; -d 1 lists the folders one level below your home folder.
• sort -h sorts those readable sizes, so the biggest folders end up at the bottom.

Run the same command on the biggest result to go one level deeper, for example du -h -d 1 ~/Library | sort -h. Add -x if you want du to stay on one disk and skip mounted volumes.

You may see "Operation not permitted" for some folders, such as Mail or Safari data. That is macOS privacy protection; Terminal needs Full Disk Access in Privacy & Security settings to read them.

The usual suspects

Once you know which folder is large, it usually turns out to be one of these:

• Downloads with disk images, installers and video files. See how to find large files on your Mac.
• Photo and video libraries, sometimes imported twice. See how to find and remove duplicate files.
• Library/Caches and app support folders that grow with use. See how to clear cache on your Mac.
• Developer folders: Xcode DerivedData, Docker's disk image, node_modules, Python environments and local AI models. See the guides on Docker disk usage, Xcode DerivedData and Ollama storage.
• iPhone and iPad backups in the iOS Files category.

Questions and answers

Why do Storage settings and Finder show different numbers?

They measure different things. Storage settings shows available space, which includes purgeable files that macOS can remove on its own, so it can look larger than the free space Finder reports. Finder and du also differ slightly, because du counts the space files occupy on disk and counts hard-linked files once.

Why do the totals change while I watch?

Storage settings calculates the categories in the background. Apple recommends waiting until every category has finished before you trust the numbers, which can take a minute or more on a full disk.

Can I delete System Data?

Not from Storage settings. Find out which app the data belongs to, using the folder sizes in Finder or Terminal, and clean it up inside that app or with that tool's own command. Deleting unknown files in ~/Library by hand risks breaking apps.

What about external drives?

Storage settings focuses on your startup disk, with a view that lists all volumes. For an external drive, open it in Finder and use Get Info, or run du -h -d 1 /Volumes/DriveName | sort -h, replacing DriveName with the drive's name.

Where is my Library folder?

Your Library is hidden in Finder. Choose Go in the menu bar and hold the Option key to show Library, or choose Go > Go to Folder and enter ~/Library. It holds app data, caches and settings, so look before you change anything in it.