7 patio estimation calculators to estimate the material needed to build a paver, concrete, or gravel patio. 7 Free Calculators: - Concrete slab - Pavers - Paver Base - Polymeric Sand - Sand & Gravel - Area - Volume Enter dimensions in inches, feet, yards, centimeters, or meters. Get results in US customary or metric measurements. Based on the calculators on Inch Calculator(www.inchcalculator.com) that are trusted by millions of people world-wide for material estimation.