Concrete Calculator
Estimate how much concrete you need for slabs, footings, and columns. Results are for planning purposes only. Confirm final quantity before ordering.
Flat concrete surfaces such as driveways, patios, sidewalks, and garage floors.
Concrete placed below grade to support walls, foundations, and other structures.
Vertical supports such as deck footings, round piers, and structural supports.
Estimated Quantity
Most concrete projects require an additional 4% to 10% over the calculated volume to account for normal jobsite conditions such as uneven grade, form variations, and minor spillage.
Planning a residential delivery? Learn more.
Call dispatch to discuss your project or request a quote online.
Concrete Calculator FAQs
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For a rectangular slab, calculate cubic yards as length (ft) × width (ft) × thickness (in) ÷ 324.
For example, a 10 ft × 10 ft slab that is 4 in thick needs about 1.23 cubic yards before waste, or 1.36 cubic yards with a 10% allowance.
Select Footing or Column / Round Pier in the calculator for those shapes. Confirm your dimensions, waste allowance and final order quantity with your contractor or dispatch before ordering.
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Short load and COD options may be available depending on location and project needs. Call Dispatch to discuss your project and delivery options.
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A cubic yard is the standard unit used to order ready mix concrete. One cubic yard equals 27 cubic feet.
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Call Dispatch to confirm your quantity, discuss your project details, and schedule delivery.
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Kienstra serves projects across the St. Louis metro area, Eastern Missouri, and Metro East Illinois, with multiple plant locations to support timely delivery.