Concrete and masonry calculators

One cubic yard is 27 cubic feet. The cubic yard calculator is the shared geometry: rectangle, circle, triangle, or an area you already measured. Concrete and asphalt start from that volume. Concrete steps are treated as solid stacked rectangles, width × tread × riser × n(n+1)/2, which is the volume of the triangular stair block.

Bag yields are the Quikrete Concrete Mix data sheet 1101 figures: a 40 lb bag makes 0.30 cu ft, a 60 lb bag 0.45, an 80 lb bag 0.60. Weight uses 150 lb/ft³ for normal-weight concrete, which is 2.025 ton/yd³. Asphalt uses 145 lb/ft³ as compacted finished thickness, 1.9575 ton/yd³. Add waste for spillage. Neither number replaces the mix ticket.