List folders / directories by size in Linux / AIX / Windows

du -sk * | sort +0nr
du -sk * | sort -nr

To list the directory sizes in Mega bytes and largest at the top
du -sm * | sort +0nr
du -sm * | sort -nr

To list the directory sizes in kilo bytes and largest at the bottom.
du -sk * | sort +0n
du -sk * | sort -n

To list the directory sizes in Mega bytes and largest at the bottom.
du -sm * | sort +0n
du -sm * | sort -n

To list the directory sizes in human readable format (Mix of kilo, Mega and Giga bytes) and largest at the bottom
du -s *|sort -n|cut -f 2-|while read a;do du -hs $a;done

To list the size of hidden directories

du -sk .[a-z]* | sort +0nr

To list the size of all the files and directorires including hidden files and directories
du -sk .[a-z]* * | sort +0n

Windows explorer Folder size extension

http://foldersize.sourceforge.net/

Download the package from the abouve URL and install it.

• · After the installation Folder Size column is available to Explorer, but Explorer isn’t displaying it yet. Open an Explorer window in Details view.
• · Right click on the column headers to see a list of columns you can add. Choose Folder Size.
• · Now we can replace the existing Size column with the new Folder Size column. Right click on the column headers and uncheck the Size column. Drag the Folder Size column header to where Size used to be.
• · Make this the default view for all folders. Go to Folder Options from the Tools menu. In the View tab, click Apply to All Folders