Why is my system data taking up so much space?

ChaseCompo wrote:

Thanks for your reply. Yes, I just realized that the available storage in settings varies from available storage within the information tab or disk utility. The settings changes a lot and seems to be very inaccurate. I wonder why that is... oh well. Just glad to know I still have more space available than previously thought.

The "System Data problem" tends to have a different solution for every individual. One aspect of this "problem" is that the disk space accounting is inconsistent in how it assigns storage space to the accounting table you are looking at. I have more 50% free space myself but was curious about freeing up more space. I found about 30 GB in old Garmin device maps that had been downloaded and installed so they were no longer needed. This were buried inside a folder in the Application Support folder. I also found two iPhone backups for phone we no longer own or use. Deleting all this freed up another 60 GB. I also found a download for an iPhone iOS update, no longer needed, some more GB saved.

It is not free but I found Daisy Disk to be an app that helps to identify such wasted space very quickly. It turns out that the purchased license allows it to be used on multiple Macs. My daughter complained her 1 TB MacBook Pro was filling up, only 50 GB free, which is dangerously far below the 15% minimum free space recommended. I used up one of my licensed installs of Daisy Disk on her Mac and she found hundreds of GB in stored Lightroom catalogs, old backups of image files that Adobe Lightroom automatically makes and saves (she processes scores of TB of image files each year for her business). She now has over 250 GB free. Her Mac is running much faster.

If you use Daisy Disk, run it as an administrator so it looks into everything. Be cautious about what you delete but the examples above were user generated files that are usually temporary but were still being stored and taking up lots of space.

There are free utilities that intend to do the same thing, show you where you are using significant disk space. I have tried most of them and ended up purchasing Daisy Disk. The others do work but Daisy Disk saves you time because it also shows how much disk space is taken up with invisible folders, protected folders, and system folders -- these are things that you should not delete, but it is useful to know how much space they take so you don't waste time looking for them and their associated disk space and instead focus on the things that you can reasonably delete. The worst utilities (like CleanMyMac) make it easy to delete things that should not be deleted, and then people post here to find out why their Mac doesn't run properly.

You are welcome

Fluctuations in space are frequently associated with System Cache files

Restarting the computer in Safe Mode

This will perform a Disk Repair, system clear cache files and only load Apple Software, extensions and fonts

The other frequent aspect re" Fluctuations is Purgeable Space which is controlled by the operating system. 

When the system needs more empty space, it moves some purgeable space to empty space.

There’s no user action to hasten this transition. It can take days or longer.

In my computer case >> there are 8 GB donated as Purgeable

As @steve626 👍 mentioned using any Third Party Disk Cleaner by any name and especially CleanMyMac aka " BrickMyMac " is not the way to deal with these types of issue

Follow on, if you please

Suggestion when checking for Used versus Free space

One of two reliable ways is to use Disk Utilities

Specifically for System Data in First Image

For General purposed in Second Image

Based upon the info in your screen shot

The Internal Drive Capacity appears to have a Capacity of 512 GB

It is reporting, still has approximately 36 % of the total 512 GB as still available for usages

That figure, is well within the generally accepted guidelines of 15% - 20 % as Empty Space

Allowing that figure to drop below that threshed of 15% - 20 % would be of concern

+1