Analyse Mac drive space usage with these tools. Don't run out of space!

Disk drives come in all sizes and some Apple MacBooks have quite small solid state drives drives. If you have an SSD, it could be nearly full and the utilities here monitor free/used space.

Solid state drives are super fast and an order of magnitude faster than old mechanical drives. They are designed for speed, but the price we pay is in limited storage space. Drives in some MacBooks have been as small as 64 GB, although thankfully none are that small anymore. They still are not big though, well, not unless you pay a small fortune for them. Entry level MacBooks still have small drives and you must keep an eye on the free space or you might fill them.

The mac has built in tools for showing drive space usage and you just need to go to the Apple menu, About This Mac and then select the Storage tab.

That's not bad and there is more information available by clicking the Manage button. However, you may find third party tools more convenient or easier to use when trying to drill down and see what files are actually using the drive space. It is always useful to know your options.

Disk Cartography

Disk Cartography - clever disk space analyzer is a free utility in the Mac App Store (search for it) that displays a list of the internal disk drives that are inside the Mac and external disk drives that are plugged into it. The used and free space is shown under each drive and there is a tiny graphic showing usage.

To the right of each drive is a Map It button. Click it and Disk Cartography scans the drive and displays the folders along with the amount of space each one uses.

Each folder can be expanded to show the subfolders and files, and the amount of space used by them is displayed. This is a handy tool for drilling down and finding what is using all the drive space. There are some useful filters that enable you to only show files over a certain size, like 16 MB as in the screenshot above. You can also choose the file type to scan for, such as photos or movies.

Disk Cartographer is simple, it works and it is free. What more do you want?

Disk Space Tab

Disk Space Tab is available in the Mac App store (search for it) and costs $2.99, although there used to be a free version - I got it when it was free. It is still only the price of a coffee though. It adds an icon to the right side of the menu bar at the top of the screen on the Mac's desktop. Click it and it displays a list of the disk drives inside the Mac and connected externally. You can see the free space, used space and a bar indicating how much space is used and how much is free.

You may find it convenient to have this mini tool in the menu bar where you can quickly check on the free space on drives. Clicking a drive icon opens a Finder window to explore the contents. Drive icons can be put on the desktop, but here they are out of the way until you need them.

The item at the bottom is a folder, not a drive and it is actually the amount of drive space used by Time Machine. If you do not have your Time Machine drive plugged in, such as when you are out of the office or home with a MacBook, Time Machine backups are saved in empty space on the internal drive. Only free space is used and there is no need to concern yourself with the space being used. It disappears when the Time Machine backup drive is plugged in.

Status menu disk

Status menu disk is a free app in the Mac App Store and it is very basic, very simple, but good enough for keeping an eye on the space used on internal and external drives on the Mac. It adds an icon to the right side of the Mac's menu bar and clicking it shows a list of drives. The green bar makes it very easy to see the used and free space.

The display is a bit too large on my 13in MacBook screen and almost reached the bottom. You probably wouldn't have this many drives though, so it may not be an issue for you. It shows the free space, important capacity and opportunistic category. It sounds confusing and it is a little bit.

Free space capacity is exactly what it says. It looks like the important capacity is the total space on the drive or partition and the opportunistic capacity is the free space minus caches and things used by macOS and apps - things that could be deleted if more space was needed.