If you want to see how much data a directory contains. Here is the command you can use.
du -sh dev
Result
746M dev
If you want to see the size of all the directory sizes…
du -sh *
Result
4.0K 2020-07-21-06-12-49.081-VBoxSVC-7899.log
34M apps
241M bin
48K CA
175M data
4.0K Desktop
746M dev
86G Documents
4.6G Downloads
4.0K id_rsa
4.0K id_rsa.pub
4.0K Music
4.0K Pictures
4.0K Public
4.0K Templates
90M tmp
4.0K Videos
0 VMs
Let’s take it a little further. What if you want to check the sizes of directories up to the second level? Here is the command you can use.
sudo du -h --max-depth=2
Result
8.0K ./.vim
4.0K ./.gnupg/private-keys-v1.d
8.0K ./.gnupg
4.0K ./Videos
620M ./dev/docker
4.0K ./Public
4.0K ./Templates
2.6G ./.local/share
2.6G ./.local
4.0K ./Pictures
<SNIP>
19M ./.mozilla/firefox
19M ./.mozilla
8.0K ./.hplip
4.0K ./Desktop
428K ./.mozc
7.1M ./tmp/nginx-1.18.0
34M ./tmp/sublime_text_3
50M ./tmp/docker-rootless-extras
90M ./tmp
96G .