How To Find Where Your Mac Storage Space Has Gone

MacBook Air And MacBook Pro Storage Space

Have you got a MacBook Air or MacBook Pro with one of Apple’s SSD (Solid State Drive) storage units installed? Then if so you have realised that you are probably running out of space on that drive. With only 120GB (or thereabouts) of storage space, it can get full very quickly. A few photos here, some music there and – what? Only 5GB left, then if this is you it’s time to act.


One program we have found to be very good (as at the time of writing this article, mid 2020) in determining where the disk space has gone is the software OmniDiskSweeper. Get it from here:

Just a word of warning always go to the company who is the originator of the software you want to download. Please do not go to or 

Backup, Backup, Backup

Before you begin to find where your Mac storage space has gone – and this is critical, so please do it, and that is to backup your Apple computer using Time Machine. Please do not run OmniDiskSweeper before finishing this essential task. Time Machine could take a while to complete if it has not backed up in a while. I would also strongly suggest that you use a less than two-year-old external Hard Disk Drive to use with Time Machine.

How To Run OmniDiskSweeper

However, the way to run OmniDiskSweeper is how I describe below.

  • Download the version applicable to your Mac Operating System. You can choose from the following (as at April 2020):

For Macs running macOS 10.13 (High Sierra) and later, click the download button to get the latest version.

For Macs running macOS 10.12, (Sierra)  download version 1.10.

For Mac OS X 10.8 to OS X 10.11, (Mt. Lion to El Capitan)  download version 1.9.

For Mac OS X 10.6 and 10.7, (Snow Leopard and Lion)  download version 1.8.

For Mac OS X 10.4 and 10.5, (Tiger and Leopard)  download version 1.7.2.

  • Install the said software and as it asks then put it in Applications.
  • DO NOT run it.
  • Instead, do the following exactly. Open Terminal (found under Utilities)
  • Once Terminal is opened type in the following exactly: sudo /Applications/
  • Hit enter.
  • Enter your computer’s password if asked.
  • A window will come up and click on the button that says “Sweep “Macintosh HD” Drive “ (By default the drive is called Macintosh HD).
  • This process can take a while on mechanical drives but on an SSD’s it usually takes a few minutes.
  • You will be presented with a list of directories with the largest directories at the top. Now be very careful in what you delete as anything in the System or Library folders is usually essential to the booting, running and working of your computer. So be 100% sure in what you are deleting here.
  • Generally speaking, it is in Applications and Users directories where the space may be taken up unwittingly. As an example under the Music directory, have a look in the following: iTunes – iTunes Media – Mobile Applications. In there you may find dozens of old apps (.ipa files). If you want to delete them you can. If you need an app again you can download it.
  • Now go to Library – Application Support – Mobile Sync – Backup. Any files here are your old iPhone backups. Double click the folder icon and Finder will reveal these files and their dates. If you want to delete what you don’t need.
  • There may be other areas you can explore but again be extra careful what you delete.

OmniDiskSweeper is a really good tool for Mac users to figure out where “lost” space may be, it’s a shame it’s not available for Windows.

If you are unsure of how to run any of the above we here at Affordable Computer Repairs and Service can do this for you, so please call us before a mistake is made. Thanks for reading!

FYI At Affordable Computer Repairs and Service in Brisbane, we repair Apple Macs, we also do malware removal, data recovery and hardware replacements.

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