Concrete Calculator

Add one pour for each distinct section, select its geometry, and enter its dimensions and quantity. The calculator converts every pour to the same base unit, sums the measured volumes at full precision, and applies the project waste allowance once after summing.

Enter the dimensions and quantity for your slab, footing, wall, or round column. The calculator normalizes the units, finds the base volume, applies your waste allowance, and converts the result to cubic yards. One cubic yard contains 27 cubic feet.

One cubic yard contains exactly 27 cubic feet. Divide cubic feet by 27 to convert a volume to cubic yards.

A 10% waste factor is a common planning starting point, but the right allowance depends on excavation accuracy, formwork, spillage, site access, and supplier requirements. Choose 0%, 5%, 10%, 15%, or enter a custom value up to 30%. Waste is applied once to the summed measured volume.

At the calculator’s nominal yield of 0.60 cubic feet per 80 lb bag, one cubic yard requires exactly 45 bags before any project waste is added. Product yields vary, so verify the yield printed on the bag before purchasing.

Yes. Add a Footing pour and enter length, width, depth, and quantity. Add another pour card for each different footing size; the project total combines them automatically.

Yes. Wall mode uses length × height × thickness. Column mode calculates a solid round column with π × radius² × height. Both modes support a quantity of identical sections.

Use Post Holes, enter the hole diameter, depth, and number of holes. If a round post occupies part of each hole, enter its optional diameter; the calculator subtracts the post cylinder from the hole cylinder. The post diameter must be smaller than the hole diameter.

The calculator compares entered bag and ready-mix prices without declaring a winner. Bags may suit small pours, while ready-mix may suit larger continuous placements. Also consider mixing capacity, placement time, access, supplier minimums, and fees that are not entered here.

Yes. Each dimension can use inches, feet, yards, millimeters, centimeters, or meters, including mixed-unit inputs. Results are shown in cubic yards, cubic feet, and cubic meters.

Divide total cubic feet including waste by the product yield and round up to a whole bag. This calculator uses nominal yields of 0.30, 0.375, 0.45, and 0.60 ft³ for 40, 50, 60, and 80 lb bags respectively, and shows the resulting excess from whole-bag purchasing.

The estimate includes the optional delivery fee you enter, but excludes taxes, short-load charges, pumping, tools, reinforcement, formwork, and labor unless a supplier has included them in the price you enter.

Choose exact volume, round up to 0.25 or 0.5 cubic yard or cubic meter, or enter a custom increment. The calculator first honors any minimum order and then rounds upward, so the supplier order is never less than the required purchase volume.