TL;DR
To fix your startup disk is full on Macbook issue:
- Clear out large files and accumulated cache to free up valuable space.
- Remove unused apps and empty the Trash to declutter your Mac and recover storage.
- Optimize your storage settings and get rid of old backups to better manage your disk space.
Tried and Tested ✅: The methods and steps mentioned in this article have been tried and tested firsthand by Ojash Yadav on his MacBook Pro M3 and rechecked for errors on Hashir’s MacBook Air M2.
Macs are great for so many things, and running out of space isn’t one of them. If your Mac is slowing down due to a full startup disk, I’ve found some easy ways to clear things up.
How to Check If Your Startup Disk is Full on MacBook
To check if your startup disk is full on a Mac, follow these steps:
- Click the Apple icon in the top left corner of your screen and select About This Mac from the dropdown menu.
- Click More Info on the window.
- In the About section, scroll down to the Storage section and tap the Storage Settings button.
- You will see a visual representation of your disk usage, with different categories like Apps, Bin, Other Users, macOS, and System Data.
- Check the colored bar representing your startup disk. If it appears nearly or completely full, your startup disk is running out of space.
❓ Did You Know?: When your startup disk is almost full, your Mac automatically slows down because it needs free space to create temporary files and run smoothly.
How to Clean Up Space on Startup Disk on Mac
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Here are some of the best ways to clean up your Mac and free up valuable startup disk space:
1. Remove Large Files on Mac
Regularly delete large and old files to free up valuable storage space and keep your Mac running smoothly. Follow these steps to delete large and old files on your Mac:
- Open a new Finder window and navigate to the location where you want to clean up, such as Documents, Downloads, or specific folders.
- Change the view to list format by clicking the View menu icon and selecting as List option.
- Click the Size column to sort the files in descending order, making it easier to identify the largest files.
- Select the files you want to delete. You can drag the selected files to the Bin or right-click the files and choose Move to Bin.
- After deleting the large files, empty your bin to remove them permanently from your Mac. To empty the Bin, right-click the Bin icon in your Dock and select Empty Bin.
2. Clear the Cache Files
Clear accumulated cache files to regain disk space and improve your Mac’s performance. Here are the steps to manually delete the cache on your Mac:
- Open Finder, click Go in the top menu bar, and select Go to Folder.
- Type the following path into the Go to Folder search bar and press Enter:
~/Library/Caches/
- This will open the Caches folder. Here, select the folder for the system data you want to clear.
- Right-click the files and select Move to Bin.
- Permanently delete the cache from your Mac by right-clicking the Bin icon and selecting Empty the Bin.
If you have MacKeeper, follow these steps to clear the cache on your Mac using MacKeeper:
- Download and install MacKeeper.
- Open MacKeeper on your Mac and click the Safe Cleanup option in the left-hand sidebar.
- Click the Start Scan button.
- Once the scan is complete, you will see a list of files that can be deleted, including Logs, Caches, Trash, Languages, and Mail Attachments.
- Check the boxes next to the files you want to delete.
- Click the Clean Junk Files button at the bottom of the window.
- This will remove the cache files from your Mac.
3. Delete Unused Apps
Uninstall applications you no longer use to free up considerable space on your Mac. To uninstall unused apps on Mac, follow these steps:
- Click the Launchpad icon in your Dock.
- Click and hold the app you want to uninstall.
- Click the X that appears in the top left corner of the app icon.
- Tap Delete to confirm.
- After deleting the app, right-click the Bin icon in the Dock and select Empty Bin.
4. Empty the Trash on Mac
Empty the Trash to permanently remove deleted files and free up disk space. Here’s how to empty the Trash on your Mac:
- Find the Bin icon on your Dock and double-click to open it.
- Click Empty in the upper-right corner of the Bin window.
- Confirm the action by clicking Empty Bin when prompted to delete all items in the Bin permanently.
5. Optimize Storage on Mac
Optimizing storage on your Mac helps you efficiently manage disk space, improve system performance, and ensure a smooth user experience. Here are some steps you can take to optimize your Mac’s storage:
- ☁️ Use iCloud: If you’re running low on storage, you can use iCloud to store your files and free up space on your hard drive. You can also use iCloud to optimize your photo storage, saving much space.
- 🖼️ Optimize Photos: Photos can take up a lot of space on your hard drive. The Photos app can optimize your photo storage by storing full-resolution versions in iCloud and smaller, optimized versions on your hard drive.
- 📂 Manage Downloads Folder: The Downloads folder can often become a repository for various files you’ve downloaded from the internet. Manage the Downloads folder on your Mac by sorting through its contents and deleting the files you no longer need.
If you’re using iCloud, you can access your files on other Apple devices and even reduce local storage by offloading files to the cloud.
6. Delete Old Backups
Remove outdated backups to free up significant storage space while keeping your most recent backups. To remove old backups on a Mac, you can follow these steps:
- Open the Finder app on your Mac.
- Click Go in the menu bar and select Go to Folder.
- In the Go to Folder window, type the following path and press Enter:
~/Library/Application Support/MobileSync/Backup/
- In the Backup folder, you’ll see a list of folders with long, random strings of letters and numbers. Each of these folders represents a backup of your iOS devices.
- Identify the backups you want to delete. You can sort the list by date modified to help you find the oldest backups.
- Drag the folders for the backups you want to delete to the Bin.
- Empty the Bin to delete the backups permanently.
7. Upgrade Your Storage
If you’ve tried the above methods and you’re still running low on storage, you may need to upgrade your storage. Here are some options:
- 🔧 Replace the Internal Hard Drive: If your MacBook has a traditional hard drive, you can replace it with a solid-state drive (SSD) for faster performance and more storage space.
- 💾 Use External Storage: You can also use external storage devices like USB or hard drives to store your files.
⚠️ Not all MacBook models allow for hardware updates. Before proceeding with any changes or modifications to your Mac, it is essential to check the specifications and compatibility of your specific MacBook model.
Clear Your Startup Disk on Mac
Once you have cleared your Startup disk, you must take some extra steps to keep your MacBook safe from any other issues. Here are some tips to improve your Mac experience:
- Consider reducing WindowServer’s high CPU usage to speed up your Mac.
- If your startup disk issues stem from a corrupted OS, reinstalling macOS can help keep your system stable and up to date.
- Freeing up RAM is another way to enhance your Mac’s performance and ensure it runs efficiently.
