It would tell you the weight and then after you put in the dimensions of the package and where it is going to, it would calculate all of your postal pricing options. Do you have a stamps.com account already?
You can sign up for a free month trial of Stamps.com and immediately use scale to weigh packages online. We have one scale on our windows PC and one to use the Internet on our MAC pc. (Stamps.com doesn't have the software available for MACs yet. I've weighed things under 5 lbs using the internet stamps.com to see how much all kinds of things weight. It's very accurate! You can't have enough of these scales! I have one at each printer.