Knowing how much storage space is available on your Mac can help you avoid installation errors, manage large files, and keep your computer organized. Whether you use a MacBook Air, MacBook Pro, iMac, or Mac mini, checking storage regularly makes it easier to identify what is taking up space before your drive becomes nearly full.
When a Mac starts displaying low-storage warnings, software updates may need more room, applications may struggle to save files, and everyday tasks can become inconvenient. Fortunately, macOS includes built-in tools that show how much storage you have used, how much remains available, and which categories contain the largest amounts of data.
In this guide, you will learn how to check computer storage on Mac, find large files, understand System Data, check external drives, and free up space safely without deleting important documents.
1. How to Check Computer Storage on Mac Using System Settings
The easiest way to check storage on a modern Mac is through System Settings. This method works on MacBook Air, MacBook Pro, iMac, and Mac mini models running recent versions of macOS.
Follow these steps:
- Click the Apple menu in the upper-left corner of your screen.
- Select System Settings.
- Click General in the sidebar.
- Select Storage.
- Wait for macOS to calculate the storage information.
The Storage screen displays a visual breakdown of used space and available capacity. Depending on your macOS version, you may also see options such as All Volumes, storage recommendations, or buttons that open details about individual categories.
The categories can include Applications, Documents, Photos, iCloud Drive, Mail, Messages, macOS, and System Data. Their names and available controls may vary slightly between versions.
This overview helps you identify whether applications, media files, documents, or system-related data are using most of your disk space. Start with the largest categories instead of deleting files randomly.
2. How to Check Storage on Older macOS Versions
If your Mac runs an older version of macOS, the storage interface may look different.
On macOS Monterey or earlier, the traditional method is to open the Apple menu, select About This Mac, and click the Storage tab. Depending on the version, a Manage button may provide additional storage recommendations.
On newer versions, the main storage view is generally found under System Settings, then General, then Storage.
If you cannot find the option immediately, use Spotlight Search by pressing Command + Space and searching for Storage or System Settings.
Once the storage window opens, allow the information to finish calculating. The numbers may change temporarily while macOS categorizes files and updates the available-space estimate.
Do not worry if your screen looks slightly different from an online tutorial. Apple sometimes changes menu layouts between macOS releases, but the general purpose of the Storage screen remains the same.
3. How to Find What Is Taking Up Space on Your Mac
Checking the total storage capacity is only the first step. If your Mac is almost full, you also need to identify the files responsible.
The Storage screen groups files into categories, helping you determine where to investigate. Select a category or its information button when available to see more details and management options.
Documents: This category may include PDFs, downloaded files, presentations, archives, and other personal documents. Look for large files you no longer need.
Applications: Review installed applications that you no longer use. Some professional applications, games, and creative tools occupy several gigabytes.
Photos: Large photo libraries and videos can use considerable space. Before removing anything, confirm whether the original files are backed up or synchronized elsewhere.
Messages and Mail: Attachments, images, and videos stored in conversations or email may gradually consume storage.
iOS files: Local iPhone or iPad backups can take up significant space. Verify that a backup is no longer needed before deleting it.
Review each category carefully. A large file is not necessarily an unnecessary file, and removing an item from a synchronized folder may also affect other devices.
4. How to Check Mac Storage Using Finder
Finder provides another way to inspect your Mac’s disk capacity and individual files.
To check the available space on your main drive:
- Open Finder.
- Choose Go from the menu bar.
- Select Computer if available.
- Select your startup disk, commonly named Macintosh HD.
- Press Command + I to open Get Info.
The information window shows the drive’s capacity and available space, although the details can vary depending on the selected volume and macOS version.
Finder is also useful for locating large files. Open your Downloads, Movies, Documents, and Desktop folders, then switch to List view. You can sort files by size when the relevant column is available.
To inspect folder sizes, use Finder’s View options and enable Calculate all sizes where supported. This may take time for folders containing many files.
Be careful when exploring hidden folders or system locations. Avoid deleting unfamiliar files from Library, System, or other protected folders simply because they appear large. Applications and macOS may depend on those files.
5. How to Check Storage on an External Hard Drive or SSD
Your Mac’s internal storage is not the only place where files can be stored. You may also use an external hard drive, portable SSD, USB drive, or other connected storage device.
To check an external drive:
- Connect the drive to your Mac.
- Open Finder.
- Locate the drive in the sidebar or under Locations.
- Select it and press Command + I.
- Review its capacity and available space in the information window.
If the drive does not appear, check the cable, connection, power supply, and Finder settings. You can also open Disk Utility from Applications, then Utilities, to see whether macOS detects the device.
Do not erase or reformat a drive just because it is not opening correctly. Formatting can remove its data. If the drive contains important files, investigate the connection and disk condition before taking destructive action.
For ongoing storage management, consider keeping large videos, archived projects, and completed backups on a separate drive. Maintain another backup of important files rather than treating a single external drive as your only copy.
6. What Is System Data on Mac, and Why Does It Use So Much Space?
System Data is a storage category that groups files macOS does not place in more specific categories. Depending on the computer and its activity, it may include caches, logs, temporary files, virtual memory files, application support data, and other system-related resources.
Its size can change over time. For example, a Mac may temporarily use more space while processing files, installing updates, or running demanding applications.
If System Data looks unusually large, begin with safe troubleshooting steps:
- Restart your Mac and check the Storage screen again.
- Install appropriate macOS updates when available and after backing up important files.
- Remove unnecessary downloads and large files you can identify.
- Review application-specific storage, such as old project files or unused development tools.
- Check whether backup snapshots or applications are contributing to storage use.
Avoid deleting random files from hidden system folders or using Terminal commands you do not understand. Some temporary data is managed automatically by macOS, and manually removing the wrong files can cause application problems or data loss.
If the reported size remains unusually high, use Apple’s support guidance or seek help from a qualified technician before attempting advanced cleanup.
7. How to Free Up Storage Space on Mac Safely
Once you understand what is using your storage, you can decide which files to remove or move.
Start with your Downloads folder. Old installers, duplicate archives, and files you no longer need may be easy to identify. Review each item before deleting it.
Next, uninstall applications you no longer use. Where possible, follow the developer’s recommended uninstallation procedure, particularly for professional software that installs supporting components.
Large video files and completed projects can be moved to external storage after you confirm that the transfer completed successfully. Keep an additional backup of important documents, photos, and work files.
You can also review Apple’s storage recommendations. Depending on your macOS version, options may include optimizing storage, managing large files, or automatically removing certain eligible items.
iCloud Drive can help make files available across devices, but cloud synchronization is not the same as an independent backup. Understand whether a file is stored locally, synchronized, or backed up before deleting it.
For additional performance advice, read our guide to improve hard drive performance. It explains practical maintenance steps that can help when a computer feels slow, although the instructions there focus on Windows rather than macOS.
8. How Much Free Storage Should You Keep on a Mac?
There is no single free-space requirement that applies to every Mac. The amount you need depends on your storage capacity, installed applications, workload, and upcoming software updates.
A Mac used mainly for web browsing and documents may need less working space than one used for video editing, software development, large photo libraries, or modern games.
As a practical approach, avoid keeping the startup disk nearly full. Leaving a reasonable amount of free space gives macOS and applications room for temporary files, updates, caches, and other operations.
For example, a Mac with a 256GB drive may become crowded quickly if it stores large videos and multiple games. A machine with a 1TB drive may have more flexibility, but it can also fill up if the user regularly works with large media files.
Check storage periodically rather than waiting for a warning. If you regularly run out of space, consider moving archived files to external storage or planning a larger-capacity device when you next upgrade.
Frequently Asked Questions
How do I check storage on a MacBook Air or MacBook Pro?
Open the Apple menu, choose System Settings, select General, and click Storage. You can review used space, available capacity, and the main storage categories from this screen.
How can I check how much storage is left on my Mac?
Open System Settings, go to General, and select Storage. You can also select your startup disk in Finder and press Command + I to inspect its available capacity.
Why does my Mac say storage is full when I have deleted files?
The Bin may still contain deleted files, storage calculations may not have updated, or other data may be using the newly available space. Empty the Bin only after checking its contents, restart if appropriate, and review the Storage screen again.
Is System Data safe to delete on a Mac?
System Data is a category rather than a single folder. Some files may be temporary, while others are needed by macOS or applications. Do not attempt to delete the entire category manually; identify the underlying files and use safe, supported cleanup methods.
Does checking Mac storage delete anything?
No. Viewing storage information in System Settings, Finder, or Get Info does not itself delete files. Deletion happens only when you take an action to remove items.
Final Thoughts
Knowing how to check computer storage on Mac makes it easier to prevent low-space problems, identify large files, and manage your digital workspace. System Settings is the simplest starting point, while Finder and Disk Utility provide additional ways to inspect files and connected drives.
Before deleting anything, verify what the file contains and whether you have a backup. Focus on unnecessary downloads, unused applications, and large personal files rather than removing unfamiliar system data.
By checking storage regularly and keeping important files backed up, you can manage your Mac more confidently and avoid unnecessary data loss or hardware upgrades.