Click on Disk Space Usage as shown above.
After a few moments the disk usage will be displayed broken down into mail, your website (public_html), and your databases (SQL).
IMPORTANT : Note that the total disk space used figure reported near the bottom (see the above example), is the total excluding the My SQL figure. To arrive at the true total usage as displayed on the front page of your Control Panel, add the two highlighted figures in the example above.
The larger number (950MB) is the current quota on your account. You can add extra disk space by emailing firstname.lastname@example.org.
To examine the usage in greater detail, check the table at the foot of the page, as shown below.
By clicking in the various items in this list it is possible to drill right down to individual files in the file manager.