System Info says my Documents folder is 170GB when Finder says it's only 8GB! Today I got a warning that my disk was running out of space, and up popped the System Information Recommendations window.  It claims my Documents folder is 170GB in size as you can see here:



But checking via Finder, the folder is only 8GB in size:



Not sure what's going on here.  In case it's relevant, my Documents folder is also synced to my Google Drive via Google Backup &amp; Sync.  Does Google maybe store "versions" hidden somewhere or something on my drive?  I've enabled invisible items and nothing significant showed up in the Documents folder, so I'm stumped.  Not sure if the 170GB number is even real or not.
Documents in the System Information pane doesn't mean files in the Documents directory.

It means files that are not other, already defined media types - ie. not photos, books, movies, etc. This would normally encompass the sort of files you'd put in your Documents folder, but they don't have to be kept in there to be part of that total.

If you actually click into Documents on that System Info screen, and then hit the File Browser button up top you'll be able to see what directories are using up the space.

Personally, I do see it's finding a large (40Gb) amount of space used in Library, which is often where things like Google cache data. Apple also caches a lot in Library.