Free Methods to Fix ‘Startup Disk Full’ Issue on Mac

Summary: Learn the manual method and the clean-up software method to resolve the ‘Startup Disk Full’ issue on Mac. You can download the free software from here to clean up the unwanted files from the Startup Disk and speed up your Mac's performance.

Recent Macs have a Solid-State Drive (SSD) as the secondary storage device. SSDs are fast but have low storage capacity. So, after a few months of usage, the free space in SSD decreases. Even Mac with a hard drive or fusion drive suffers from insufficient storage space after a certain period.

The reduced space on the Startup Disk results in freezing, crashing, or slowing of your Mac. Also, macOS throws the ‘Startup Disk Full’ error when the free space reduces beyond its limit. Relax. Go through the following troubleshooting methods to fix the “Startup Disk full” issue on macOS.

1. Manage Storage Drive on Your Mac

You can check how much storage space is used by different file types in macOS and manually manage your Mac storage drive. Steps are explained next:

a) Go to Apple menu > About This Mac. A window opens that shows the overview of your Mac.


b) Click the Storage tab. The screen graphically shows the storage space according to file types.


c) Click the Manage tab. From the left pane, you’ll see automatic recommendations for clean-up.


d) The right pane allows you to Store in iCloud, Optimize Storage, Empty Trash Automatically, and Reduce Clutter. Click the corresponding button to perform the required task.


e) From the left pane, click the Applications option to know all the installed applications on your Mac storage drive on the right pane. Uninstall unneeded applications from here.

f) Click the Documents option from the left pane to know which documents and folders use the most storage. Select a tab—Large Files, Downloads, or File Browser—from the right pane. For instance, from the Downloads tab, click the cross (x) icon on any unneeded file to remove it.


g) From the File Browser tab, secondary click any unneeded item and select Move to Trash.

h) Select the iOS Files option from the left pane to permanently erase device backups and software updates to free storage space on your Startup Disk.

i) Select the iTunes option from the left pane to remove movies, TV shows, and podcasts that you can download again to free storage space on your Startup Disk. From the right pane, select the Open iTunes button.

j) From the Library tab, choose a file type from the left pane, secondary-click any item from the right pane, and choose Delete from Library.

k) Select the Mail option from the left pane and remove junk mails to regain Startup Disk space.

l) Select the Trash option from the left pane to browse your Trash folder. You can remove individual items or click the Empty Trash button from the top-right corner to free up Startup disk space.

2. Delete Duplicate Files from Startup Disk

Mac Startup Disk should have sufficient free space to make it work correctly. You can free up Startup Disk space by deleting all duplicate files from your Mac. Steps are as follows:

a) From the Menu Bar, go to File > New Smart Folder.

b) In the window, click the + sign located at the top-right corner to add a new filter.

c) Change the filter parameters to include any file kind. Locate duplicate files.

d) Keep the original files and select all the duplicates, secondary click, and choose Move to Trash.

e) Perform the duplicate file removal task for other file kinds.

f) After all duplicates are recovered, open Trash and check all deleted files, then Empty Trash.

Also Read: How to Remove Duplicate Files from Mac for Free?

3. Remove Caches and Logs from Mac

You can remove caches and logs from your Mac to free up Startup Disk space. Steps are as follows:

a) From the Menu Bar, navigate to Go > Go To Folder.

b) In the Go to Folder textbox, type ~/Library/Caches and click Go.

c) Open each folder one by one, delete all the cache files, and then empty your Trash.

d) From the Go To Folder, type ~/Library, and click Go To remove log files.

e) Find the Log folder. Open the folder and delete the log files of apps that you don’t use.

f) Open Trash and check if you have any important files to restore, and then Empty Trash.

Once you perform the above solutions, your Mac Startup Disk will regain free space and function properly without any slowdown errors. You need to perform these methods time and again to optimize free space on your Mac Startup Disk.

4. Clean-Up Software Method to Free Up Startup Disk Space

The manual clean-up task is monotonous and requires your time and energy. There is a better workaround for this tedious task. You can use a Mac clean-up software to remove junk, duplicate, and large files with a click of a button. Steps to free up Startup Disk space are as follows:  

a) Download and install the free SpeedUp Mac software on your iMac, MacBook, or Mac mini.

Free for 30 Days

b) Launch the software and select Macintosh HD from the left panel of the software interface.


c) Press the Scan button to initiate the scanning process on Macintosh HD, the selected drive.


d) See the total file size that the software can clean. Select the required files from the checkbox.

e) Click the SpeedUp Now button to remove Cache Files, Log Files, Trashes & Leftovers, System Junk, and Language Files from your Mac Startup Disk.


f) Let the software to perform the cleaning task on the Mac Startup Disk.

g) Click OK on the Process Completed dialog window.

*SpeedUp Mac software comes with complete functionality for 30 days without any cost. You can activate the software any time before the due date to continue using it.


Mac Startup Disk can fill up with stored applications and data after a particular time. The low free space can result in the Startup Disk Full error on your Mac. You can eliminate the error by removing inessential applications, downloaded files, duplicate data, caches, and logs from your Mac, then empty Trash after verifying its stored content.

The above manual process might seem doable to free up storage space on Startup Disk for one or more times, but it is not helpful if your Mac runs out of Startup Disk space frequently. SpeedUp Mac software can automate the clean-up task at a scheduled interval and save your time and energy in such a situation.

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