There is also a great ncdu utility – it can show directory size with detailed info about subfolders and files.

Installation

Ubuntu:

$ sudo apt-get install ncdu

Usage

Just type ncdu [path] in the command line. After a few seconds for analyzing the path, you will see something like this:

$ ncdu 1.11 ~ Use the arrow keys to navigate, press ? for help
--- / ---------------------------------------------------------
.  96,1 GiB [##########] /home
.  17,7 GiB [#         ] /usr
.   4,5 GiB [          ] /var
    1,1 GiB [          ] /lib
  732,1 MiB [          ] /opt
. 275,6 MiB [          ] /boot
  198,0 MiB [          ] /storage
. 153,5 MiB [          ] /run
.  16,6 MiB [          ] /etc
   13,5 MiB [          ] /bin
   11,3 MiB [          ] /sbin
.   8,8 MiB [          ] /tmp
.   2,2 MiB [          ] /dev
!  16,0 KiB [          ] /lost+found
    8,0 KiB [          ] /media
    8,0 KiB [          ] /snap
    4,0 KiB [          ] /lib64
e   4,0 KiB [          ] /srv
!   4,0 KiB [          ] /root
e   4,0 KiB [          ] /mnt
e   4,0 KiB [          ] /cdrom
.   0,0   B [          ] /proc
.   0,0   B [          ] /sys
@   0,0   B [          ]  initrd.img.old
@   0,0   B [          ]  initrd.img
@   0,0   B [          ]  vmlinuz.old
@   0,0   B [          ]  vmlinuz

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