In order to find the amount of free disk space in your Ubuntu, you can use the df command.
df
The df will display the amount of disk space available on your file system containing each file name and argument. If no file name is given, the space available on all currently mounted file systems will be shown.
The output of executing df command:
root@my-server:~# df
Filesystem 1K-blocks Used Available Use% Mounted on
udev 483032 0 483032 0% /dev
tmpfs 250088 1024 249064 1% /run
/dev/vda1 25226960 4892352 20318224 20% /
tmpfs 500168 0 500168 0% /dev/shm
tmpfs 5120 0 5120 0% /run/lock
tmpfs 500168 0 500168 0% /sys/fs/cgroup
/dev/loop1 69504 69504 0 100% /snap/lxd/22753
/dev/vda15 106858 5321 101537 5% /boot/efi
/dev/loop10 48128 48128 0 100% /snap/snapd/16010
/dev/loop5 116736 116736 0 100% /snap/core/13308
/dev/loop3 44928 44928 0 100% /snap/certbot/2133
/dev/loop11 48128 48128 0 100% /snap/snapd/16292
/dev/loop8 44928 44928 0 100% /snap/certbot/2192
/dev/loop4 116736 116736 0 100% /snap/core/13425
/dev/loop7 63488 63488 0 100% /snap/core20/1581
/dev/loop9 63488 63488 0 100% /snap/core20/1587
tmpfs 100032 0 100032 0% /run/user/0
Alternatively, you can use df with -h option:
df - h
With -h option, df will print sizes in human readable format (in powers of 1024 e.g., 1K, 150M, 2G)..
Example output of executing df -h:
root@my-server:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 472M 0 472M 0% /dev
tmpfs 245M 1.0M 244M 1% /run
/dev/vda1 25G 4.7G 20G 20% /
tmpfs 489M 0 489M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 489M 0 489M 0% /sys/fs/cgroup
/dev/loop1 68M 68M 0 100% /snap/lxd/22753
/dev/vda15 105M 5.2M 100M 5% /boot/efi
/dev/loop10 47M 47M 0 100% /snap/snapd/16010
/dev/loop5 114M 114M 0 100% /snap/core/13308
/dev/loop3 44M 44M 0 100% /snap/certbot/2133
/dev/loop11 47M 47M 0 100% /snap/snapd/16292
/dev/loop8 44M 44M 0 100% /snap/certbot/2192
/dev/loop4 114M 114M 0 100% /snap/core/13425
/dev/loop7 62M 62M 0 100% /snap/core20/1581
/dev/loop9 62M 62M 0 100% /snap/core20/1587
tmpfs 98M 0 98M 0% /run/user/0
