How to clear 'System Data' taking up too much space on my iMac?

My System Data is out of control. I read tips about what to do, and I get to a point where it's "Don't delete any files that may impact your Mac." I'm at my wits end. Any help would be immensely appreciated.


[Edited by Moderator]

Original Title: Please help; it's closing in and I can't breathe

iMac 24″

Posted on Jul 18, 2025 9:00 PM

Reply
Question marked as Top-ranking reply

Posted on Jul 19, 2025 12:12 AM

FWIW personally I never look at System Data because it is so misleading.


Instead, I look at "available" in some Finder window's Status bar at the bottom (View > Show Status Bar).


Or via Disk Utility's "Free" info which is more accurate. While you are in Disk Utility, also set View > Show APFS Snaphots and check if, for example, Time Machine has accumulated them when its backup drive has been disconnected.


Extra mobile device backups might also accumulate at ~/Library/Application Support/MobileSync/Backup and extra mail attachments taking space at ~/Library/Mail.


Why is my system data taking up so much s… - Apple Community


System data on Mini Mac 1 - Apple Community


What is system data and why I can't clean… - Apple Community


5 replies
Question marked as Top-ranking reply

Jul 19, 2025 12:12 AM in response to abess35

FWIW personally I never look at System Data because it is so misleading.


Instead, I look at "available" in some Finder window's Status bar at the bottom (View > Show Status Bar).


Or via Disk Utility's "Free" info which is more accurate. While you are in Disk Utility, also set View > Show APFS Snaphots and check if, for example, Time Machine has accumulated them when its backup drive has been disconnected.


Extra mobile device backups might also accumulate at ~/Library/Application Support/MobileSync/Backup and extra mail attachments taking space at ~/Library/Mail.


Why is my system data taking up so much s… - Apple Community


System data on Mini Mac 1 - Apple Community


What is system data and why I can't clean… - Apple Community


Jul 19, 2025 2:13 AM in response to Matti Haveri

Matti Haveri wrote:

FWIW personally I never look at System Data because it is so misleading.

Instead, I look at "available" in some Finder window's Status bar at the bottom (View > Show Status Bar).

Or via Disk Utility's "Free" info which is more accurate. While you are in Disk Utility, also set View > Show APFS Snaphots and check if, for example, Time Machine has accumulated them when its backup drive has been disconnected.

Extra mobile device backups might also accumulate at ~/Library/Application Support/MobileSync/Backup and extra mail attachments taking space at ~/Library/Mail.

Why is my system data taking up so much s… - Apple Community

System data on Mini Mac 1 - Apple Community

What is system data and why I can't clean… - Apple Community

+1

Jul 19, 2025 1:30 AM in response to abess35

I would strongly suggest follow both the advise from @ Matti Haveri as well as reading from the link they were so kind to supply


The computer in question appears to be a 24" iMac ? that can come figured with a 256GB SSD as it can come configured with a larger drive


Would we be correct in thinking, because you are so concerned with /System/Volume/Data taking 222.11 GB of space


That this machine has the Entry Level 256 GB drive or possible the 512 GB drive ?


In either case and only after you have exhausting All possibilities provided by my colleague


The more  popular and effective ways to address this issue is to Start Over from Scratch 


For Apple Silicon computer >> Use Disk Utility to erase a Mac with Apple silicon.


Always make a Time Machine Backup  before  proceeding 


It is also suggest to  Only Migrating the User Account and nothing more.


Emphasis on User Account Only


Reinstall the Needed, not the Wanted applications from the Apple Apps Store or Directly from the Developers 



This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

How to clear 'System Data' taking up too much space on my iMac?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.