System Data at 114 GB AFTER deleting other files....

Since System Data includes user generated files for any numbers of apps, as well as snapshots for Time Machine, those can rise and fall every day, on their own.

My computers have between 60 GB and 100 GB of System Data, it can vary from day to day. 114 GB might still be in the normal range.

You can delete the Time Machine snapshots from within Disk Utility. But they eventually get recreated and come back.

After deleting files, it can sometimes take a day or two from the drive to reorganize the storage space and show it as free.

256 GB seems inadequate for normal computing nowadays. I think that used to be the lowest end model and I don't think that is even offered anymore.

You might consider getting a utility like DaisyDisk or Storeograph which will provide much more detailed information about where your storage is going. I have used DaisyDisk and it helped me eliminate tens of GB I didn't need, but I also have 1 TB storage in my laptop, more than 50% is free. I just obtained Storeograph and it looks like an excellent product.

You might try a Safe Mode boot.

Start up your Mac in safe mode - Apple Support

Use the instructions in the section labeled, "Start up in safe mode (Mac with Apple silicon)."

Once you achieve Safe Mode, walk away for 20-30 minutes to give Safe Mode time to do its housekeepng chores. Then do a normal restart and see if the system size decreased.

No one seem quite sure what cause system bloat. I've heard a number of things tossed about, among them:

— files generated by unneeded anti-virus and so-called "cealning" apps

— Google Chrome

— Temp files generated but some printer software.

We don't know at this point. Steve's suggestion of a disk inspector app is wise.

A bit more on what steps you can take ...

One of my Macs shows 116 GB of System Data. But the Storage tool attributes only 27 GB to Photos, yet I have over 178 Gb in my Pictures folder, mostly a number of different Photos Libraries. My System Photos Library is about 29 GB, so it seems the Storage tool is counting only that for Photos (but it says 27 GB which is oddly a bit smaller than the 29 GB for that Library). So what about the rest of my 178 GB of Photos Libraries? I think it is mostly in what is called "System Data," but even that is too small so some must be bookkept somewhere else. Maybe in Documents, which is shown as 211 GB but my Documents folder is only 35 GB. So you can see that the Storage tool is not very precise in its categories, and System Data turns out to be sort of a catch all.

The tools I mentioned, DaisyDisk and Storeograph, do show you exactly where your storage is being used up.

To save on internal disk storage, you can move all the contents of the Pictures folder to an external drive. Same thing can be done for Music files and libraries. But then you will need to purchase external drives, plus additional external drives to back up those contents. In the end, it might have been cheaper just to get a Mac originally with 512 GB or 1 TB storage. And it is unfortunate to saddle a small and light laptop with multiple external drives just to keep your files handy. But you are where you are and these are things you can do.

You can also utilize cloud storage to reduce you use of internal storage. But in any of these approaches, take into consideration the need to have backups of everything important where you can quickly and easily access them.

avery_a wrote:

My Mac (Macbook Air 2022, M2, Sonoma 14.3.1) was running out of space so I decided to clean stuff up. The 87 GB of system data seemed daunting so I focused on other things.

Yes, it is daunting.

I deleted over 10 GB of media attachments from Messages

Good idea.

and optimized iCloud which did free up space, only for System Data to shoot up to 114 GB,

Fascinating isn't it. Unfortunately iCloud can be part of the reason System Data gets larger when you choose "Optimize Storage". It is complicated. I know respected forum contributor @etresoft has mentioned people getting into a never ending battle trying to get out of a low storage situation and I seem to recall him mentioning iCloud being part of the problem with that battle loop.

@steve626 mentioned the third party app Storeograph which was created by @etresoft. This app was written specifically to help people with storage issues on macOS. While I haven't used the paid features of this app yet, the video demonstration on their website certainly looks like it would be a very good app as it tries to educate users about macOS storage. I haven't seen any other app with such specific knowledge regarding macOS storage and APFS file system behavior.

which is pretty ridiculous. My Mac is 256 GB, how is this normal? It's been almost a day and I've restarted my computer too, but the number remains the same. Help.

Think about it this way. After you boot the computer & before you start any workloads.....I highly recommend you have at least 80GB - 100GB of Free storage space.......perhaps even more depending on your specific workloads. I have found that 80GB can disappear very quickly these days and I am not doing much on my Mac. I find macOS doesn't always release storage & memory as quickly as it should (or at least as quickly as I would like anyway) which leads to that 80GB disappearing. And if your Free storage space gets below 20GB, then you are in for some serious trouble.

FYI, the only place you can get the actual Free storage space value is in Disk Utility....it will be shown on the right side just below the bar graph. Ignore the very misleading "Available" storage shown everywhere in macOS (including in Disk Utility....left side in the table below the graph). In macOS "Available" is not synonymous with Free.

If you happen to show the storage values for external volumes mounted on the Desktop, you will be confused even more since "Free" value shown on the mounted volumes icons on the Desktop is not the same Free space value shown in Disk Utility.....leave it to Apple to be inconsistent & misleading here (I only just discovered this flaw the other day while assisting another user).

Unfortunately people purchase computers with too little internal storage which leads to these storage related problems. It is possible to relocate some large items (usually macOS libraries such as Photos, Movies, and Music) to external media. If you deal with large volumes of data, then maybe once you are done with the project you can relocate those projects to external media in order to make room on the internal SSD for the next project.

Move your Photos library to save space on your Mac - Apple Support

Move your iMovie for Mac library - Apple Support

Change where your music files are stored on Mac - Apple Support

You do have to keep in mind that deleting data or moving data to external media may not immediately increase the Free storage space due to how the APFS file system works with backup snapshots which may retain the deleted/moved data for up to 48 hours after the backup has been transferred to external media.

It is my considered opinion that  Apple should have never made MBAs with the punny 256 GB Capacity Drive 

This type of drive capacity in 2026 would be equivalent to the 128 SSD available in the past.

Great for internet browsing, emails, messages and light word processing , spread sheet etc

But Multimedia file retention, not so much

However and in defence of Apple, they did make available a Customized Configuration is available for 512GB, 1TB, or 2TB.

Despite these options, the /System/Volume/Data remains a mystery regarding the best practices for pruning it.

For reference, here are some related issues from other users:

* System data is consuming too much space in MacOS Sonoma.

* Time Machine Local Snapshot won’t delete.

* Over 60% of storage is blocked by System Data.

* Running out of storage after upgrading to macOS Tahoe 26.2.

Just to add two other places to check out and try and save space

* System Settings > General > Storage > Scroll to the bottom and look for macOS.

* To the right of the macOS notice, click the “i” in a circle.

* You may find Apple Intelligence using several GB of storage.

* Turning off Apple Intelligence may save space, but it defeats its purpose.

Another interesting development regarding newer versions of Google Chrome is that it can be stopped from downloading a hidden 4GB AI file.

One other thing I forgot to mention

Although you have deleted " 10 GB of media attachments from Messages "

From another contributor @etresoft regarding Free Space and Available Space 

Free vs available disk space huge differe… - Apple Community

Quote >>  “ The "available" storage is the amount of used storage that the operating system could automatically delete if it felt that it was really necessary. The "free" storage is the amount that you can actually use for something.

There are system processes that run in the background and automatically delete some of the "available" storage and convert it to "free". If you completely run out of storage, then those system processes will try a little harder. When you "delete" files you are just hinting to the operating system that you don't need those files anymore. The operating system will eventually remove them, but on its own schedule.

Certain tools will allow you to force the issue and manually clean up some of this storage and manually delete local snapshots. But that is only temporary. "  << End Quote 

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

Get detailed information about a disk in Disk Utility on Mac

avery_a wrote:

The 87 GB of system data seemed daunting so I focused on other things. I deleted over 10 GB of media attachments from Messages and optimized iCloud which did free up space, only for System Data to shoot up to 114 GB, which is pretty ridiculous.

And exactly as designed. "System Data" isn't system data. It's just "other" data that can't be classified as something else. So when you delete over 10 GB from a first-tier classification category like Messages, you transfer over 10 GB from the "Messages" category to the "System Data" category. iCloud is very similar. When you "optimized" iCloud, you transferred that storage to "System Data".

My Mac is 256 GB, how is this normal?

How? "How" is very similar to "why" and we can't answer those kinds of questions in a user-to-user tech support forum. What you've described is 100% normal and 100% expected behaviour.

It's been almost a day and I've restarted my computer too, but the number remains the same. Help.

Give it another day and you might get that 10 GB back.

But if you have a 256 GB computer, this could be an ongoing challenge, depending on about 2 dozen other settings.

> deleted over 10 GB of media attachments from Messages and optimized iCloud which did free up space, only for System Data to shoot up to 114 GB

Ironically, deleting files does not free up disk space - at least not immediately.

Files in common locations such as ~/Downloads or ~/Documents are easily categorized.

However, when you delete them, the OS does not automatically delete the files and recover the space - they're retained in disk snapshots to facilitate recovery (in case they were deleted accidentally).

Guess where these snapshots are categorized? You got it - as 'System Data'.

So deleting files will have a corresponding increase in the System Data usage metric.

The OS will automatically maintain these snapshots and delete the oldest ones as necessary (including backing up to external media via Time Machine), so over time the space used by these 'deleted' files will be available again, but that could be hours, or days, or even weeks, depending on your setup and usage.

For the most part - don't sweat 'System Data'. There is a core amount of space that is required, but much of it is transient/temporary data that the OS will maintain and clean up automatically. Unless you're running into single-digit numbers of free space on your drive, just let the OS do its thing.