We just got a message that SharePoint online is out of storage space. Is there a way to get an overview of file size and location across all our sub-sites similar to WinDirStat or DaisyDisk? That would make it a lot easier to figure out where to start culling.
I would go into the admin portal, https://yourtenant-admin.sharepoint.com and see what sites are taking up a large amount of space. From there you can navigate to the site and go to
/_layouts/15/storman.aspx and this will tell you where the bulk of the storage is being used. Go to the library and prune.