Concrete Stairs Calculator
Estimate the material in a solid set of uniform concrete steps with a flat underside. The tool sums the stepped cross-section instead of treating the stair as one rectangular block.
How the calculation works
For n equal steps, stepped cross-section area = tread run × riser height × n(n + 1) ÷ 2. Multiply by stair width. Convert all inches to feet first, then divide cubic feet by 27.
Worked example
Five solid steps, 4 ft wide, with 10 in tread run and 7 in riser height contain about 29.17 ft³ or 1.08 yd³. At 10% extra, that is 1.19 yd³ or 54 bags at 0.60 ft³ yield.
Before you order
This geometry assumes the space below the steps is filled with concrete. A sloped underside, void, landing, thickened base or separate foundation changes the volume. Confirm the formwork and structural details with your plans.
Review the calculation method and source notes, then use the supplier checklist before placing an order.
Continue planning
Content and calculator by pourmeasure. Formula and assumption notes: methodology and sources. Updated October 2026. No independent engineering review is claimed.