Rectangular slab: Length × Width × Thickness × Quantity
Round column or hole: π × (diameter ÷ 2)² × depth × quantity
The loss rate is added after the net volume calculation is completed. The number of bags is rounded up according to the output of each bag, so the actual purchased volume is usually slightly higher than the volume including losses.
The result is a materials procurement estimate, not a structural design. Please check the on-site dimensions, design thickness, base flatness, product output per bag and supplier requirements; complex or load-bearing projects should be reviewed by professionals.
View QUIKRETE’s official concrete dosage calculation instructionsChoose a rectangular slab or round column, enter its dimensions and add a waste allowance. Enter the actual yield printed on your bag because products vary.