Easily Calculate square footage. Enter up to 12 dimensions for a quick and easy calculation. Calculate how much aggregate or material you need in cubic yards. This calculator can be used for any aggregate, soil, or mulch. How much mulch do you need for your landscaping? How much loam do you need for your garden? How much stone do you need for an extra parking space? These questions can be answered easily! All you need is the square footage for the location the material will be used and the thickness at which it will be applied.