How To Add File and Folder Counts to a library
SharePoint has some basic functionality for showing the number of items in folders. These are columns that already exists in your library--you just have to display them in the view.
- In your library, go to the 'All Documents' view and edit the view.
- You can also select any current column heading, then select 'Column Settings'-'Show/Hide Columns'
Look for File Size, Item Child Count, or Folder Child Count and select them to have them show up as columns in the view.
Choose which works best for you.
File size: does a complete count of all items (folders and files). At the document level, this will switch to showing individual file size
Item child count: only counts files
Folder child count: only counts sub-folders
To see the total number of items (files and folders) in a document library, go to Site Contents