Density can be measured by either the metric or standard units of measurement, I am going to use metric in this example. In order to calculate the density of a solid object you will need to know two variables. First you need the measurement of the mass of the object, usually measured in grams. Secondly you need to know the volume of the object in cubic centimeters. You can find this measurement

. easily for simple shaped objects, but if it is not a basic shape you may have to use the displacement method to discover the volume. When you have these numbers divide one into the other. That's your density calculation. You can find more information here: http://www.ebsinstitute.com/Baseball/EBS.crp2df.html