Report how much space is used and available in storage in ZFS on FreeBSD

zfs list

Use the list option on the zfs command built into FreeBSD.

zfs list

Example:

$ zfs list
NAME                 USED  AVAIL  REFER  MOUNTPOINT
zroot               4.41G  17.4G    88K  none
zroot/ROOT          3.49G  17.4G    88K  none
zroot/ROOT/default  3.49G  17.4G  3.15G  legacy
zroot/tmp            112K  17.4G   112K  /tmp
zroot/usr            947M  17.4G    88K  /usr
zroot/usr/home       184K  17.4G   128K  /usr/home
zroot/usr/ports      947M  17.4G   947M  /usr/ports
zroot/usr/src         88K  17.4G    88K  /usr/src
zroot/var            792K  17.4G    88K  /var
zroot/var/audit       88K  17.4G    88K  /var/audit
zroot/var/crash       88K  17.4G    88K  /var/crash
zroot/var/log        348K  17.4G   348K  /var/log
zroot/var/mail        92K  17.4G    92K  /var/mail
zroot/var/tmp         88K  17.4G    88K  /var/tmp
$ 

Learn more on the zfs man page. The zfs command has many options for controlling the rich features of the ZFS file system.