How to see disc usage from cp

Without going into linux commands, is there a simple button or area in the Linode cp that shows you how much of a disc image is being used? I know it will show you how much of your Linode account is being utilized by images, but can it show you how much of an image is being utilized by data (in other words, like Windows tells you about your local drive).

This info is needed to be able to determine how small the images can be resized down to.