Is there any app or method to see what made a Mac’s disk storage grow or shrink? It seems like every week or so, Finder shows my available storage has jumped or shrunk by more than a few GBs. Yesterday, it went from around 100GB free to about 3! That was an emergency, and yet I knew of no quick way to tell what caused it. The culprit turned out be the huge default cache of a newly installed app, Mountain Duck. But it took a few minutes to figure that out. There must be a quick way to see what caused such a jump.
OmniDiskSweeper may meet your needs.
Or GrandPerspective, which was just updated.
Thank you, Adam and Tommy for your helpful answers! … So much more helpful than the scolding responses over at another site.
Let me add to the question: What I realize would be the most helpful feature is the ability to compare a disk’s present state with a snapshot from earlier. Does anything come to mind?
Scolding? That’s silly—you had a perfectly reasonable question. OmniDiskSweeper and GrandPerspective are free, so they’re they best place to start, but there are other apps along these lines too, like Daisy Disk, which I haven’t used, but many people like.
And CleanMyMac can also help.
For the most part, these apps will only show you the state of disk usage. If you want something to alert you when you use up a lot of disk space unexpectedly, CleanMyMac might be able to do that (can’t remember), or you could install something like iStat Menus, which has graphs for things like disk usage.
Both CleanMyMac and iStat Menus are available in Setapp, which might be a useful way to get access to them and many other apps.
Following on from Adam’s reply mentioning DaisyDisk (which I haven’t used either), it’s currently $4.99 rather than $9.99 via BundleHunt:
You can use the Finder to see what has changed. I just updated Numbers and there it is.
Use Command-F, select “This Mac”. Enter nothing in the search field. Just add Search options like I show in this screenshot. As you see here, I sort by size. You can experiment with sorting
and with the options under “Last modified date” or use “Created date”. If System Files are not an option, click on “Other” and search for it.
If you click on a file you can see where it is placed
There might be some files that are hidden from the Finder, but that is very few. And there are a lot of changes in 24 hours, 2500+ in this case. But there is a high probability you will find what you are looking for if it is big or many.