How to check Mac storage, five ways.

1. How to check storage on Mac in System Settings

This is Apple's main storage view, and the one to start with.

1. Open Storage settings. Choose Apple menu › System Settings, click General in the sidebar, then click Storage. Or press Command-Space and type “Storage.”
2. Read the bar. Wait for it to finish calculating. Each color is a category, like Applications, Documents, Photos, macOS, and System Data. The number above it is how much is available.
3. Look inside a category. Scroll down and click the info button next to a category to see its files, sorted by size, with the option to delete them.

One category won't open up this way: System Data, the gray slice near the end. What is System Data on Mac explains what's in it.

2. About This Mac

Choose Apple menu › About This Mac, then click More Info. That opens System Settings › General › About, where the Storage row shows something like “142 GB available of 494 GB.” Click Storage Settings there to jump to the full view above. On macOS 12 and earlier, About This Mac had its own Storage tab.

3. Finder

• The status bar. Choose View › Show Status Bar, and every Finder window shows how much space is available at the bottom.
• Get Info. Choose Go › Computer, select Macintosh HD, and press Command-I. The window shows capacity, available, and used.
• Folder sizes. Open a folder in list view (View › as List), choose View › Show View Options, and turn on Calculate all sizes. Click the Size column to sort. Start with your home folder: this is the quickest way to see which folders are big.

4. Disk Utility

Open Applications › Utilities › Disk Utility, and select Macintosh HD in the sidebar. You'll see used, free, and capacity for the whole disk, including other volumes in the same container. Disk Utility won't break usage down by category, but it's the place to check an external drive too.

5. Terminal: how to check disk space on Mac precisely

For exact numbers, open Terminal and run:

df -h /System/Volumes/Data

Read the Avail column. Use /System/Volumes/Data, not /: since macOS Catalina, / is the read-only system volume, so df -h / shows only a few gigabytes used even when your disk is full. To list the biggest folders in your home folder:

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

The biggest are at the bottom. Run the same command on ~/Library/* to go one level deeper; it's where caches, app data, and developer files live. The first time, macOS may ask whether Terminal can access folders like Documents and Desktop. Allow it, or those folders are skipped.

Why the numbers don't match

• Purgeable space. Finder and Storage settings count space macOS can free on demand, like local snapshots and iCloud files it can download again, as available. df doesn't. On the Mac this guide was written on, df showed 32 GB available while macOS counted 270 GB available for important files.
• GB versus GiB. Finder counts 1 GB as a billion bytes. df -h counts in gibibytes, about 7 percent larger, so a 994 GB disk shows as 926Gi.
• Timing. Storage settings measures when you open it and can lag behind what you just deleted. Give it a minute.

How to see what's taking up space on Mac

Start with the biggest category in Storage settings. If it's Applications, Documents, or Photos, its info button lists the files. If it's System Data, the space is in places Storage settings doesn't name, and the System Data guide shows how to reclaim it. If nothing stands out, sort your home folder by size in Finder, and look inside ~/Library, ~/Downloads, and any code or video folders.

How to find large files on Mac

1. In Storage settings. Click the info button next to Documents to see large files and downloads, sorted by size.
2. In Finder. Press Command-F, click This Mac, change Kind to Other, choose File Size, and set it to “is greater than 1 GB.”
3. In Terminal. Spotlight's index answers in seconds:

   mdfind 'kMDItemFSSize > 1000000000'

   Or search your home folder directly, which is slower but includes files Spotlight skips:

   find ~ -type f -size +1G 2>/dev/null

Found more than you expected? The free up space checklist goes through what's safe to remove, in order.

Memory vs storage on Mac

They're easy to mix up because both are measured in gigabytes.

• Memory (RAM) is the workspace apps use while they run. It empties when you quit apps or restart. About This Mac shows how much you have, and Activity Monitor › Memory shows how much is in use.
• Storage is the SSD that keeps your files, apps, and macOS itself when the Mac is off. Everything in this guide checks storage.
• They meet in swap. When memory runs short, macOS moves some of it to storage. That's why a nearly full disk can bring up “Your system has run out of application memory,” even on a Mac with plenty of RAM.