How to See Which Folders Take the Most Space on Your Mac

Your Mac says the disk is almost full, and Storage settings tells you that "Documents" or "System Data" weighs 200 GB. That doesn't tell you which folder to open. To find the folders that actually take the space, you need a view that measures folders, not categories.

The short answer: in the Finder, switch a window to list view, choose View › Show View Options, tick Calculate all sizes and click the Size column header. In Terminal, du -sh ~/* | sort -h ranks the folders of your home folder by size. And a disk space analyzer such as Space Lens in Folia Files draws a whole folder as bubbles, so the biggest ones stand out at a glance and you can dive into them. Here is how each method works, and when to use which.

Why Storage settings doesn't show folders

System Settings › General › Storage sorts your disk into categories: Applications, Documents, Photos, Mail, iCloud Drive, macOS, System Data and so on. The ⓘ buttons open some of them, and the one next to Documents lists your large files. That's useful for a quick win, but a category isn't a place: "Documents" can mean a video project in Movies, a forgotten folder in Downloads and a virtual machine somewhere in your Library.

If the mystery is System Data specifically, we explain what's inside it in What Is System Data on a Mac?. This article is about the step that comes before or after: finding the heavy folders, wherever they are.

Method 1: folder sizes in the Finder

Get Info for one folder

Select a folder and choose File › Get Info (⌘I). The Size line is calculated after a moment. It's accurate, but you check one folder at a time, which is slow when you don't know where to look.

Calculate all sizes in list view

By default the Finder shows "--" instead of a size for folders. To fix that:

1. Open a Finder window, for example your home folder (⇧⌘H).
2. Switch to list view (⌘2).
3. Choose View › Show View Options (⌘J) and tick Calculate all sizes.
4. Click the Size column header to put the biggest items first.

Then open the biggest folder and repeat. The setting applies to the window's folder; click Use as Defaults in the same panel to have it everywhere. On a large folder, sizes take a while to appear, and the list re-sorts as they come in.

Method 2: measure folders in Terminal

Terminal gives you a precise ranking in one command. To rank the folders and files at the top of your home folder:

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

The largest come last. To go one level deeper in a folder, for example your Library, which the Finder hides:

du -hd 1 ~/Library 2>/dev/null | sort -h | tail -15

-d 1 limits the output to one level of subfolders, and tail -15 keeps the 15 biggest. Two things to know:

• 2>/dev/null hides the "Operation not permitted" errors for folders macOS protects (Mail, Safari, other apps' data). Those folders are then simply not counted. To measure them, give Terminal Full Disk Access in System Settings › Privacy & Security.
• du on your whole disk can take minutes and mixes in system files you shouldn't touch. Start with your home folder: that's where the space you can free usually is.

Method 3: see every folder at once with Space Lens

Lists and commands work, but you read sizes one line at a time. A disk space analyzer shows proportions instead. Space Lens in Folia Files draws the folder you're in as bubbles: the bigger the bubble, the more space it takes. Folders are measured as soon as you open it, with the same items listed by size.

Open it on any folder

• In any pane, choose View › Disk Usage (⌘6), or click the bubbles button in the pane header. Space Lens measures the folder that pane is showing.
• To measure a whole disk or a folder that isn't open, choose Tools › Space Lens…; Other Folder lets you pick another one.

Dive in and come back

Click a folder's bubble to go inside it; the path at the top takes you back to any level, and the arrows work like Back and Forward. Double-click an empty area to go up one level. Right-click a bubble for Explore, Show in Pane, Show in Finder or a Quick Look preview, so you can check what a file is before deciding anything.

Select, review, then send to the Trash

Click a file's bubble, or tick items in the list, to select them: the bar at the bottom adds up what you've chosen. Review and Delete opens one last list of everything selected with its size, and Move to Trash sends it there. Nothing is deleted outright: until you empty the Trash, you can put things back, and ⌘Z undoes the move.

See what grew since last time

Space Lens keeps each scan (the last 12 per folder). When you scan a folder again, a button at the top shows how much it grew or shrank since an earlier scan; click it for What Changed, the list of the folders that moved the most. That's the quickest way to find the folder that keeps filling your disk week after week.

Folder sizes in the normal list

You don't have to switch views to compare folders. In Folia Files, list view calculates folder sizes on local disks by default (Settings › Panes › Calculate folder sizes (local disks)), so View › Sort By › Size or a click on the Size column header ranks folders right away, in any pane.

Good to know

• Cloud folders (iCloud Drive, Dropbox, Google Drive…) are not scanned by default, so files that only live online don't inflate the numbers. The option is in Settings › General.
• Without Full Disk Access, the folders macOS protects are left out, as with du.
• Space Lens is in both the website edition and the Mac App Store edition. In the App Store edition, Apple's sandbox limits Folia Files to the disks and folders you've opened to it; it asks when needed.

Where the big folders usually are

Once you can see sizes, the same suspects come up on most Macs:

• Downloads: installers, disk images (.dmg), archives and videos you only needed once.
• Movies and Pictures: video projects, screen recordings, exports. Your Photos library is a single package in Pictures; manage it from the Photos app, never by deleting items inside it.
• Library › Application Support and Library › Containers: data from apps, including ones you deleted long ago. To remove an app with everything it left, see how to completely uninstall a Mac app and its leftovers.
• Library › Developer: Xcode simulators and build folders, often tens of gigabytes on a developer's Mac.
• Old iPhone and iPad backups, virtual machines and music libraries.

Before you delete anything

A big folder isn't necessarily a useless one. Before you send a folder to the Trash, open it and look at what's inside. If it belongs to an app, remove it from that app or uninstall the app properly. If it's a project or media you may want again, move it to an external disk instead. And leave the System folder and the hidden folders at the root of the disk alone: macOS manages them itself.

Measure, open, check, then delete: with a view that shows folders by size, finding what fills your Mac takes minutes, not an afternoon.