Startup Disk Full on Mac

Everyone keeps their house clean, but surprisingly, many Apple users neglect to clean their devices even when their disk is full on Mac. The result? An annoying "Your disk is almost full" notification and quite possibly poor MacBook or iMac performance.

Don’t worry, we’ve got you covered. Our guide will show you how to check if your startup disk is full and how to free up essential space by clearing your Mac.

Before we start

 

The best way to prevent any lagging when you first turn on your device is to clean up startup disk on Mac regularly. Maintaining an uncluttered startup disk is crucial to ensure your device is optimized, but it can take a lot of effort to keep on top of your disk maintenance. With the help of MacKeeper’s Safe Cleanup, the tiresome task is all done for you.

 

Here’s how you can leverage MacKeeper's Safe Cleanup feature:

1. Download MacKeeper and install it.
2. Open the app and choose Safe Cleanup from the left panel menu.
3. Click Start Scan.
4. You can then tick which Logs, Cache, and Trash you want to remove and then click the button Clear Junk Files to finalize the process.

What is the startup disk on Mac

The startup disk is the hard drive or SSD that holds the operating system for your MacBook. For most people, this is the built-in drive on their Mac. And unless you set up an external drive, it’s probably also the place where all your other local files and data are stored.

This means your documents, downloads, and other items are all probably saved to your startup disk, alongside macOS and every other app installed on your computer. However, you should mind that overloading your internal storage can cause lagging and poor MacBook optimization. Therefore, to avoid any performance issues, we advise you to clean up the startup disk on Mac.

Hint from our experts: 

 

Unfortunately, most modern Macs don’t usually let you upgrade the startup drive to give you more storage. So if your startup disk is full on Mac, the only way to fix it is to clear out data to create more free space.

What does it mean when a disk is full on Mac

If your Mac pops up with the notification message “Your disk is almost full,” it’s almost certainly referring to your Mac’s startup disk.

A full disk on your Mac signals a critical storage issue with your MacBook or iMac’s built-in hard drive. When you see the disk is full on Mac message, it means that your device’s startup disk has exhausted all its available space due to the accumulation of redundant files and applications.

This congestion not only hampers your Mac's speed but can also hinder essential operations, such as saving additional items or installing essential macOS updates. Thus, before you make space on the startup disk on your MacBook, first find out what exactly is causing the issues.

Note from our team: 

 

Keep a close watch on your MacBook notifications, as these alerts can remind you when it’s time to declutter a MacBook.

Why is your startup disk full on your Mac

If your startup disk is full on Mac, there can be many culprits that often lead to unexpected storage challenges. The most common offender is the accumulation of unnecessary files, apps, and system data. Over time, this gradual build-up consumes valuable space on your MacBook and iMac startup disk, impacting the overall performance of your Apple device. Meantime, the build-up of unnecessary files isn’t the only reason your disk is full on Mac—check the results of our investigation below.

Common reasons for a full startup disk include:

• Junk files and cache that often accumulate from old documents and old downloads all still clutter and take up valuable space.
• Applications that are rarely or never used will still occupy storage space on your Mac, contributing to a full startup disk.
• Duplicates of data and files, including documents and photos, can be scattered across your system, unnecessarily consuming your disk space.
• Old macOS files that are only meant to be temporary can linger and add to the overall clutter on your startup disk.

How to check startup disk on Mac

Even if your Mac hasn’t sent you a notification to say that the startup disk is full on Mac or close to full, you should still regularly check how much free space you’ve got left. That way, you can promptly fix any problems as they develop.

Here’s the easiest way to check the free space on your Mac:

1. Open System Settings.
2. Click on General >  Storage and wait for the chart to load, showing you how much of your Mac’s storage is being used and by what.

You’ll then see the name of your Mac’s startup drive — usually labelled as Macintosh HD. You’ll be able to hover your cursor over the chart to find a breakdown of the total storage being used and how. Ideally, you want to keep about 20GB of storage space available.

How to clear startup disk on Mac

Reclaiming enough space on your Mac's startup disk is essential for maintaining optimal performance. If you find yourself dealing with no space, you’ll need to take proactive steps to clean up the startup disk on a Mac.

Here are all the best methods we’ll guide you through to help you clean up startup disk on Mac:

• Check and empty trash
• Delete old downloads
• Clear cache
• Backup large files
• Delete duplicate photos
• Delete mail downloads
• Uninstall unused applications
• Delete unused languages
• Clean your desktop
• Optimize your storage
• Remove old iOS backups

Keep a close watch on your MacBook notifications, as these alerts can remind you when it’s time to declutter MacBook.

1. Check and empty trash

The Trash folder on your Mac regularly fills up with useless data and files over time. Unless you empty it, the Trash bin will continue to accumulate and store everything you ever deleted. Don’t be surprised if your Trash folder is eating up valuable space on your startup disk. The solution is to clean up the startup disk on Mac by emptying your Trash bin regularly.  

Here’s how to check and empty Trash to make space on your startup disk on MacBook:

1. In your Dock, right-click on Trash Bin
2. Select Empty Bin.

You should find that this creates much more free space on your startup disk. If so, you might want to learn how to tell your Mac to automatically empty the Trash every 30 days.

2. Delete old downloads

Deleting old downloads is a crucial step should you need to clean up a startup disk on Mac. Over time, these accumulated files can take up significant space, contributing to a full disk. When you delete downloads, you not only make room for essential files but also enhance your Mac's overall performance.

Here’s how you can delete old downloads:

1. Navigate to the Downloads folder in Finder.
2. Sort downloads by date to identify old files.
3. Select unnecessary downloads for deletion.
4. Move selected files to the Trash.
5. Click on Empty inside your Trash Bin to permanently free up space.

3. Clear cache

If your startup disk is full on Mac even after deleting old downloads, you may still have lots of hidden system files using up your storage. Of course, you want to keep hold of all the essential data while still deleting unnecessary system files, including log files, but doing this job manually can be incredibly time-consuming. Moreover, if you get it wrong, you could even cause problems with macOS.

Nevertheless, if you’re sure you want to clear cache manually, here are the steps to guide you:

1. Open Finder and select Go > Go to Folder from the menu bar.
2. Visit the following file paths to look for any caches you can delete (don’t delete any caches with “Apple” in the name):
   • ~/Library/Caches/
   • /System/Library/Caches/
3. If you find any you think are safe to remove, highlight them and right-click. This will bring up the pop-up menu, allowing you to select Move to Bin.
4. Then right-click on Trash Bin and click Empty Bin to permanently clear the cache.

For simplicity, it’s quicker and easier to use software like MacKeeper’s Safe Cleanup to automatically find and safely remove all unnecessary system items and cache for you. Here’s how:

1. Download MacKeeper and install it.
2. Open the app and choose Safe Cleanup from the left panel menu.
3. Click Start Scan.
4. You can then tick which Logs, Cache, and Trash you want to remove and then click the button Clear Junk Files to finalize the action.

4. Back up large files

Backing up large files is a pivotal step to help prevent the notification your disk is full on Mac from appearing due to low storage. One of the most reliable ways to do this is to utilize Time Machine on Mac. Time Machine can create a backup of all your large files to ensure that valuable data isn’t lost or accidentally deleted.

Ready to back up your large files with Time Machine? The steps below will help you:

1. Click on the Apple Icon and choose System Settings.
2. Select General > Time Machine.
3. Click Add Backup Disk or click the (+) button.
4. Ensure your preferred storage device is connected and click Set Up Disk.

5. Delete duplicate photos

It’s also possible that to make space on startup disk MacBook, you need to delete duplicate photos that are taking up essential space on your Mac. This sometimes happens due to software bugs that copy files in the background, without you knowing. Luckily, with the help of MacKeeper’s Duplicates Finder, duplicate photos are easy to clear up. Check the steps below:

1. Open the MacKeeper app and choose Duplicates Finder.
2. Click the Start Scan button to allow MacKeeper to automatically scan for duplicate photos and screenshots on your Mac device.
3. Once the scan is complete, you can look through the findings and tick all the items that you want to remove.
4. Click Confirm to finalize the removal of duplicate photos from your MacBook.

6. Delete mail downloads

Deleting mail downloads is crucial if you need to make space on startup disk in MacBook. This storage-saving solution isn’t only a reliable method of clearing up vital Mac space but can also enhance overall device performance, ensuring optimal functionality.

Here’s how to delete mail downloads and help clean up a startup disk on Mac:

1. In Finder, click Go > Go to Folder.
2. Type in the path: Library and search find your Mail folder.
3. Inside the Mail folder, search Attachments.
4. You may see several folders, all titled Attachments. Review the files inside and delete the ones you don’t need.
5. Right-click Bin in your Dock to Empty Bin to remove all mail downloads.

Manually deleting mail downloads can be a tricky and time-consuming process. Clearing the wrong files from your MacBook or iMac could cause you to lose essential data or system files that can’t be recovered. If you do, you may need to perform a factory reset on Mac to reinstall the critical system files back onto your device.

7. Uninstall unused applications

To free up space, you can uninstall an app on your Mac that you no longer use. This is a simple yet effective way to optimize and clean up the startup disk on Mac. Follow the steps below to uninstall unused applications:

1. Open Finder and select Applications to view all the apps on your Mac.
2. Review the list and pinpoint any apps you no longer use or need.
3. Drag the unwanted apps to your Trash.
4. Right-click on the Trash icon in your Dock and select Empty Trash.

Pro tip: 

 

For a more reliable way to clean up a desktop on a Mac, we recommend MacKeeper's Smart Uninstaller to help you remove unwanted apps. Unlike the manual method, where you could easily delete the wrong files, our uninstaller tool ensures a safe and thorough cleanup. Download MacKeeper today to enjoy pain-free device maintenance.

8. Delete unused languages

Efficiently managing your Mac's storage can include deleting unused languages, which can help make space on a startup disk. By removing any unused language files on your MacBook, you free up disk storage and enhance system performance, preventing the dreaded “disk is nearly full on Mac” notification.

Here’s how to delete unused language files:

1. In Finder, go to Applications.
2. Right-click on an app and choose Show Package Contents.
3. Navigate to Contents > Resources inside the application package.
4. Identify language folders with their codes (e.g., "en.lproj" for English).
5. Drag any unwanted language folders from the app into Trash.
6. Right-click on the Trash icon and select Empty Bin to free up space permanently.

9. Clean your desktop

Optimizing your device if your startup disk is full on Mac can include decluttering your desktop. This is a pivotal step in enhancing both organization and performance, as cleaning your desktop of unnecessary data can contribute to a more efficient and responsive system.

Here are some tips to help clean your Mac’s desktop:

• Review the files you have on your device and identify any you don’t need or use.
• Organize and group related items into folders for a more streamlined desktop.
• Use stacks to organize files automatically
• Move unwanted files into Mac Trash and remember to click Empty Bin.
• Change icon size, grid spacing, and even text size.

10. Optimize your storage

To help make sure your MacBook or Apple iMac has ample storage space, ensure there’s enough disk space available for essential updates, downloads, and general daily activities. Here’s how you can proactively optimize your Mac storage:

1. In System Settings, go to General > Storage
2. Click on the Info button to see exactly how much space each app is taking on your Mac.
3. View the recommendations and decide how to optimize storage on your Mac:
   • Store in iCloud: You can keep files from your Desktop and Documents folders in iCloud to help optimize your Mac storage. That way, you’re only keeping recently opened items on your Apple device.
   • Optimize Storage: If you watch movies or shows from Apple TV, then it’s recommended you remove the ones you have wanted to help optimize your storage. Also, keep an eye on your email attachments, leaving only the ones that are most recent or necessary.
   • Empty Trash Automatically: You can also erase any items that have been sitting in your Trash for a while, and it’s good if you do this regularly.

Advice from our experts: 

 

For a more efficient optimization, give MacKeeper's Memory Cleaner a try. This innovative tool provides a comprehensive approach to optimizing your Mac's storage and startup disk, ensuring a smoother and faster experience.

11. Remove old iOS backups

For our final solution to help clean up your startup disk on Mac, we recommend removing old iOS backups. You’d be surprised just how much storage is being used by local iOS or iPadOS backups. If you don’t need these backups anymore—which might be the case if you now back up to iCloud—you can easily delete them. Here’s how:

1. Open Finder, and click on your device.
2. Under the General tab, click Manage Backups to see a list of your backups.
3. From here, right-click on the backup that you want, then select Delete or Archive.
4. Click Delete Backup, then confirm.

Automatically keep your startup disk clean with MacKeeper

The ongoing battle to defeat the dreaded ‘disk is full on Mac’ notification isn’t always easy to resolve, as manually optimizing your MacBook or iMac can take time and a lot of sifting through dozens of folders. Thankfully, there's a solution to help make the process much less painstaking.

By leveraging a reliable Mac disk cleaner like MacKeeper, the initial concern while cleaning up a startup disk on Mac is a worry of the past. In particular, MacKeeper’s Safe Cleanup ensures your startup disk stays clean without requiring constant manual intervention. You can even enable the Auto-scan feature to let MacKeeper work in the background and bid farewell to the woes of a cluttered startup disk.