Aurionix FileUsage is a Windows Explorer add-on that adds 3 additional info columns to the Detail View. The extra columns display the total size of all files and subfolders within a given folder, the total percentage disk usage as well as the total number of files within a given folder. (You will need to restart your computer and add the new columns to the Detail View).

The license of this software is Freeware, you can free download and free use this shell extension software.