Driveway Concrete Calculator
Calculate concrete needed for a standard driveway (40x12 feet, 5 inches thick).
feet
feet
inches
Volume (Cubic Yards)
7.41 cu yd
Slab Area480.0 sq ft
Volume (Cubic Feet)200.00 cu ft
With 10% Waste8.15 cu yd
Volume (Cubic Yards) vs Slab Length
How to Calculate Concrete for a Slab
Formula
Volume (cu ft) = Length (ft) x Width (ft) x Thickness (ft)
Volume (cu yd) = Volume (cu ft) / 27
First convert thickness from inches to feet by dividing by 12. Standard slab thicknesses are 4 inches for patios and walkways, 4-6 inches for driveways, and 6-8 inches for heavy-duty applications.
Example Calculation
A patio slab measuring 20 ft by 12 ft with a 4-inch thickness.
- 01Convert thickness: 4 inches / 12 = 0.333 ft
- 02Volume = 20 × 12 × 0.333 = 80 cu ft
- 03Cubic yards = 80 / 27 = 2.96 cu yd
- 04With 10% waste = 2.96 × 1.10 = 3.26 cu yd
- 05Order 3.5 cubic yards from the concrete plant.