How to Show Folder Sizes in Finder on Mac

Open a folder in Finder's list view and the Size column shows real numbers for files but a useless -- for every folder. Finder skips folder sizes by default because adding up a folder's contents takes work. One checkbox turns it on — per folder, or everywhere at once.

Turn on "Calculate all sizes"

1. Open the folder in Finder and switch to list view — press Cmd+2 or choose View → as List. The setting only exists in list view.
2. Choose View → Show View Options, or press Cmd+J.
3. Check Calculate all sizes.

The -- entries start filling in with real sizes. Finder computes them in the background, so a folder holding a node_modules directory or years of photos may take several seconds — the numbers appear as they finish. Once calculated, click the Size column header to sort largest-first and see instantly where your space went.

If there is no Size column at all, Control-click any column header and check Size to add it.

Apply it to every folder

Checked on its own, Calculate all sizes affects only the folder you were viewing. To make it the default everywhere:

1. With the View Options panel still open (Cmd+J), click Use as Defaults at the bottom.
2. Every folder you view in list view from now on calculates sizes. Folders you previously customized keep their own settings — revisit them and check the box, or see our guide to resetting per-folder view options.

Is the always-on setting worth it? On any Mac with an SSD, yes — the calculation is fast and cached. The one place you might skip it is a huge network share, where totting up folder sizes means pulling metadata across the network every time you browse.

Quick checks without changing anything

Two ways to get a folder's size on demand, no settings involved:

• Get Info: select the folder and press Cmd+I. The Size line shows the total and the item count. Select several folders and press Option+Cmd+I for a single combined-total window.
• Terminal: du reports disk usage for anything:

# human-readable total for one folder
du -sh ~/Downloads

# size of each item inside it, sorted largest last
du -sh ~/Downloads/* | sort -h

Both are read-only — nothing to undo. Note that du measures space actually used on disk, which can differ slightly from Finder's number for cloud-synced or sparse files.

Why the numbers sometimes disagree

Finder shows sizes in decimal units (1 GB = 1,000,000,000 bytes), so a folder can look bigger in Finder than in tools that use binary units. iCloud Drive folders with "optimized storage" can also report a logical size far larger than the space used locally — the Get Info window shows both figures ("on disk"). If a folder seems impossibly large, that is usually the explanation, not corruption.

Found something huge?

Sorting by size usually surfaces a few surprise multi-gigabyte folders. Before you delete anything, read our guide to finding large files on your Mac — it covers the built-in storage tools that break usage down by category and age.