Dropbox is using 605 GB of disc space in (user)/Library/Cloud Storage/Dropbox

Question

My M2 MacBk Air, running Sequoia 15.7.7 had been running around 700 GB disc usage on its 1 TB HD.  Recently is suddenly started giving me "Disc almost full" warnings.  It's at 895 GB of 995 available and my "System Data" is a colossal 675 GB! (should be around 50 GB normally).  After some hard searching, I found at: Users>[username]>Library>Cloud Storage>Dropbox (only folder in Cloud Storage) that this Dropbox folder contains 605 GB of data!  (my problem!).  I've never looked at this folder before but this must be something new I would think.  I'm using Dropbox Plus with 2 TB of storage of which I'm only using about 700 GB.  I am using the service that backs up my Document & Desktop folders, but I've been doing that for quite awhile.  I looked for some kind of cache that wasn't emptying, but I think this folder is where my space problem is.  I'm not entirely clear about how the backup works, but I don't think this folder I've spotted is caching backup is it?  From the folders IN that Dropbox folder w. 605 GB, it look like this is just my regular Dropbox, but I didn't check and compare size between these sub-folders and their namesakes in my actual Dropbox in the App.  Anyone have any insight into what's going on here?    Any suggestions?  All comments greatly appreciated!

Jay · Answer

Could you check the Sync and storage dashboard in the Dropbox desktop application, and attach a screenshot here (while hiding any personal information) to show us what you see there?

WillyJP · Answer

Well forgive me if I'm a bit hazy in my understanding of how this all works!  But here's a few facts:  My Documents Folder is 516 GB "on disc" and my Desktop Folder is 92 GB "on disc" (totaling 609 GB).  My Dropbox Folder is shown under "Locations" (and my Mac HD is another line there) as if it's NOT "on disc" BUT it's size is reported as 620 GB "on disc" by Finder.  So by my rough calculation my Dropbox (as opposed to my Document & Desktop backups) is only about 12 GB.  So, I'm confused about what's going on here.  It appears to my admittedly sketchy understanding that I have a Dropbox folder on disc (at Users>(my username)>Library>Cloud Storage>Dropbox) that contains, in addition to my Dropbox stuff (that is in there to share with my family) a full backup copy of my Document & Desktop folder.  Apparently in addition to the online backup of them that I know is there because I can access those to Mac folders in Dropbox on my phone.  I really don't want to make any of my Document or Desktop folders be "online only" IF I can avoid it, but it appears that the duplication on disk of my two backup folders is accounting for my space problem because it is taking up a duplicate 609 GB with those two duplicated folders.  Now maybe I'm missing something about how I set this up or something.  I agree with what you say that my backup part of Dropbox shouldn't be taking up extra disc space (a cache for uploading being a different matter of course).   I'd really appreciate it if someone could explain to me how to get back that ~600 GB of my 1 TB HD so I wouldn't keep getting "almost full" messages from my Mac!!  All suggestions gratefully received!!

Jay · Answer

Hi @WillyJP, thanks for messaging the Community.

The Dropbox Backup feature backs up specific folders to your Dropbox account online, and shouldn't take up extra space on your machine, only on your Dropbox quota on the site.

Have you marked any of the files in your Dropbox folder as online-only to free up space?

This will help me to assist further!