Determining The Complete Size Of A Folder & Its Sub-Folders in Finder?

Solution 1:

In Finder:

  1. Either:
    1. Option + click a folder.
    2. Or: Click the gear icon in the header.
    3. Or: Select the View menu, and then "Show View Options".
    4. Or: Command + J
  2. Select "Show View Options"
  3. In the 4th subset of options select the box "Calculate all sizes".

If a folder is empty it will only show "--" like all the folders previously did.

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