Thanks for this! Found this article after a short Google search on the topic :)

One thing I note is that the file size reported is in Gibibytes — I had to convert to Gigabytes in order to get the figure more commonly shown when hitting CMD + I on a file or directory.

Using this method to play a bit of hard drive tetris and figure out the most space efficient way to store a bunch of large directories across a couple external drives, and this accurate way of getting directory sizes without having to manually CMD + I every directory to get its size is a life saver!

Looks neat. However, when I try it on ruby 2.3.7 I get

/Users/jonathan/bin/sizes:273:indirectory?': no implicit conversion of nil into String (TypeError)`

Neat. FYI, I hit an error at first, because I was in a directory with a path like /Users/max/Dropbox (Personal)/src/foo/bar. I added an additional call to Shellwords.escape when shelling out to ls and then it worked.

I use the following alias:

alias duf='du -sk * | sort -n | while read size fname; do for unit in k M G T P E Z Y; do if [ $size -lt 1024 ]; then echo -e "${size}${unit}\t${fname}"; break; fi; size=$((size/1024)); done; done'

Picked it up from http://www.earthinfo.org/linux-disk-usage-sorted-by-size-and-human-readable/ which no longer exists. :-(