If the Find Duplicate Files checkbox is checked, folders are also scanned for duplicate files.
If you only want to find folder sizes, it will be much quicker if you uncheck this box
before scanning any folders.
To find the total disk space used by all the files in a folder, and in all subfolders under it, simply select the folder in the Folder Browser with the left mouse button and select the Scan Folder command. For more information on scanning folders, follow this link.
The total disk space used by all files in a folder (and all subfolders) is shown in square brackets next to the folder name. If the square brackets next to a folder name are empty, it means the size for that folder is still being calculated.
If the Find Duplicate Files checkbox is checked, folders are also scanned for duplicate files.
If you only want to find folder sizes, it will be much quicker if you uncheck this box
before scanning any folders.