Get Info on Mac HD shows incorrect free space

Peter Russell1 wrote:

Get Info Info on Mac HD not working properly.

If you actually did "Get Info" on the actual volume such as "Macintosh HD", then you can calculate the actual Free storage space from the information provided:

Free space = Available space - Purgeable space

Otherwise the only place where the actual Free space is shown is in Disk Utility or the System Profiler. These days on macOS "Available" is not synonymous with Free.

It shows 35GB free out of 1TB - after I "Deleted Immediately" about 50 GB from Trash. Grand Perspective showed 820Gb used.

I permanently deleted another 60GB but Get Info still shows only 35Gb free. Whereas Grand Perspective now correctly shows 760GB used.

Like @etresoft mentioned, storage is complicated on macOS these days with the APFS file system and the more recent versions of macOS.

FYI, even the Used storage space value is complicated where under certain circumstances the Used space may be larger than the physical drive itself due to how the APFS file system works. Keep in mind third party apps may be calculating storage differently from macOS....may be a good thing, may not be a good thing depending on perspective. The Free storage space value provided by macOS is the only value which really matters.

Reducing System/Volume/Data is a common question. 

1 -  System data taking too much in MacOS Sono… - Apple Community

2 - Time Machine Local Snapshot won't delete - Apple Community

3 - Over 60% storage blocked by System Data - Apple Community

How to free up ‘System Data’ and other storage on your Mac from a fellow colleague  @ neuroanatomist

View APFS snapshots in Disk Utility on Mac

Suggest getting an External SSD Drive and start moving your Pictures, Videos, Music and any other large files you have control over, OFF the Internal drive and Onto the External

Understanding iCloud Drive from a well written User Tip from @ Richard.Taylor

There are  two effective ways to remedy this issue:

1. Quick Fix Actions:

 For Apple Silicon computers, use Disk Utility to erase a Mac.

 For Apple Intel computers, use Disk Utility to erase an Intel-based Mac, then reinstall macOS.

 Always make a Time Machine backup before proceeding.

 Migrate only the user account, not the entire system.

   Reinstall only the necessary applications from the Apple App Store or directly from the developers.

2 - Generally

Note - On Apple Silicon and newer computers. The SSD Drive and the Unified RAM are Soldered to the Logicboard and can not be upgraded.

Peter Russell1 wrote:

Any thoughts?

It's complicated. You actually can't delete anything "immediately". You can't delete anything at all. All you can do is flag a file for deletion at a later date when the Apple "deleted" task gets around to it. Usually that happens in a day or two, assuming no other problems.

But that last bit can be a big assumption. Usually when people get into this state, they have multiple problems. For example, I know for a fact that Get Info will NEVER tell you how much free storage you have. It only tells you "available" storage. You don't have 35 GB free. You probably only have 3 GB free. So your system is going to be struggling to do just about anything, with will likely further delay that "deleted" task.

Two cents here

Purgeable Space is controlled by the Operating System and not the user 

Get detailed information about a disk in Disk Utility on Mac

Building on the previous posting regarding possible larger Free Space issues

One of the few accurate methods to evaluate Used Space versus Free Space

Is to use Disk Utilities >> View all Devices

If it should report that there is less than about 15% to 20% of the Total Drive Capacity as Free Space

Some have a different take on the amount of Free Space and suggest a minimum of 100 GB as Free Space

There is a handy tool outside Grand Perspective

Perhaps using Storeograph  that can be downloaded Direct from the Developer or from the Apple Apps Store

Disk Utilities

Peter Russell1 wrote:

Disk Utility shows 25GB taken up by "other volumes." I don't have any other volumes mounted. What might this apply to?

That sounds like the size of the boot volumes.

I will defer to @etresoft

If I understand this Volume is the sealed and read-only volume which is the Boot Volume