Running out of storage on your Mac can slow down performance and cause app errors. Learning how to see disk space accurately helps you manage files and keep your system responsive.
Use the overview below to compare the most common methods for checking available space on macOS.
| Method | Where to Find It | Level of Detail | Best For |
|---|---|---|---|
| Apple Menu > About This Mac > Storage | Apple menu in the top-left corner | Graphical overview by file category | Quick visual summary |
| Finder > Go > Computer > Internal Drive | Finder sidebar or Go menu | File-level browsing | Finding large files manually |
| About This Mac > Manage | Storage tab in the same window | Recommendations and categories | Cleaning up system files |
| Terminal: df -h / | Applications > Utilities > Terminal | Raw filesystem data | Advanced users and scripts |
About Storage Management in macOS
macOS includes built-in tools that show how much disk space is used and where it goes. These tools help both casual users and power users keep their systems organized.
Checking Overall Disk Space the Simple Way
You can view total disk space and available space in just a few clicks using the Apple menu.
Using the Apple Menu
Click the Apple logo in the top-left corner, choose "About This Mac," then select the Storage tab to see a color-coded breakdown of used space.
Using About This Mac Storage Bar
Clicking on any category in the storage bar opens a more detailed view that suggests ways to free up space, such as reducing clutter or optimizing storage.
Viewing Available Space for Every Volume
If you have multiple drives or partitions, you can check each one individually using the Finder.
Using the Finder Sidebar
In any Finder window, press Command+Shift+C to jump to the Computer view, where internal and external disks appear. The sidebar shows available bytes for each volume at a glance.
Using Get Info
Select a disk in the Finder, press Command+I, and you will see total capacity, available space, and used space for that specific volume.
Managing Files to Free Up Space
Beyond checking numbers, you need a strategy to remove or offload files that you no longer need regularly.
Storage Recommendations
Open Apple menu > About This Mac > Manage to let macOS suggest actions like storing files in iCloud, reducing clutter, and emptying the Trash automatically.
Maintain a Healthy Mac Drive
Regular monitoring and scheduled clean-ups keep your Mac fast and prevent surprises when storage runs low.
- Check disk space at least once a month using About This Mac > Storage
- Review the Manage recommendations and apply safe cleanup steps
- Move large archives and old projects to an external drive or cloud storage
- Empty the Trash and clear Downloads folder weekly
- Keep a few gigabytes free for system updates and temporary files
FAQ
Reader questions
How do I see disk space for an external drive on Mac?
Open Finder, press Command+Shift+C, locate the external drive in the Computer section, and check the available space shown in the sidebar or press Command+I to open Get Info.
Why does macOS say my disk is full when I still have free space?
This can happen when system files, hidden caches, or Time Machine snapshots are using space that the basic view does not highlight immediately.
What does Optimize Storage do in macOS?
Optimize Storage in the Storage Management window removes local movie and TV files that you have already streamed and moves rarely used apps to the cloud when possible.
Can I run these checks from Terminal instead of using the GUI?
Yes, you can use commands like df -h / for a quick overview or ncdu in Terminal to scan directory sizes for precise control over large folders.