Concrete Stairs Calculator
Cubic yards for solid poured steps against a stoop or slab. Enter the riser height, tread depth, how many steps and the width; add a top landing if the steps end in a platform. Solid steps use a lot of concrete — fill the core with rubble or block on tall runs.
Buy 40 × 80 lb bags — under 1 yd³ bagged mix beats a short load.
- Net volume (21.4 ft³)
- 0.79 yd³
- Waste 10%
- + 0.08 yd³
- Ready-mix ticket
- 1.00 yd³
- Approx. weight
- 3,208 lb
- 80 lb bags
- 40
- 60 lb bags
- 53
- 40 lb bags
- 79
- Materials + delivery$130–$185 / yd³ · Sep 2026
- $255 – $310
- Installed (with labor)typ. $977
- $691 – $1,443
Quantities follow the ticket. Links may earn us a commission at no cost to you; they never change a number.
What will this stairs job cost?
See the installed price range for these quantities and get up to 3 quotes from local contractors. Free, no obligation.
How to calculate stairs by hand
Cubic feet = Width (ft) × Run (ft) × Rise (ft) × n(n+1)/2 + Width × Landing depth × Rise × n
Worked example
- Each step k is a block k risers tall and one tread deep; summing 1 + 2 + 3 + 4 = 10 tread-blocks.
- One tread-block: 4 ft × (11 in ÷ 12) × (7 in ÷ 12) = 2.14 ft³.
- Four steps: 2.14 × 10 = 21.4 ft³ = 0.79 yd³.
- Waste 10%: 23.5 ft³ = 0.87 yd³ → 40 × 80 lb bags, or a 1 yd³ short load.
- 3 steps, 4 ft wide, 7″ × 11″
- ≈ 0.5 yd³ · 24 × 80 lb bags
- 4 steps, 4 ft wide
- ≈ 0.8 yd³ · 40 bags
- 5 steps, 4 ft wide
- ≈ 1.2 yd³ · ready-mix
- 6 steps, 5 ft wide
- ≈ 2.1 yd³ · ready-mix
Questions crews ask
How much concrete do I need for steps?
Solid steps are a stack of blocks: step k is k risers tall and one tread deep. Volume = width × run × rise × n(n+1)/2, all in feet. Four 7″ × 11″ steps 4 ft wide come to 21.4 ft³ = 0.79 yd³; with waste order a 1 yd³ short load or 40 × 80 lb bags.
How many bags of concrete for 3 steps?
Three 7″ × 11″ steps 4 ft wide are 12.8 ft³; with 10% waste 14.1 ft³ → 24 × 80 lb bags, 32 × 60 lb or 47 × 40 lb. Right at the edge where a short load is worth pricing.
What is the standard rise and run for concrete steps?
7″ rise and 11″ run is comfortable and code-compliant nearly everywhere: the IRC allows up to 7¾″ rise and a minimum 10″ tread. Keep every riser within ⅜″ of the others — uneven steps are the most common inspection failure.
Do I have to pour stairs solid?
No. On runs over 3–4 steps, form a hollow core with compacted gravel, rubble or block and pour a 4–6″ shell over it; that can halve the concrete. The calculator gives the solid volume — subtract your fill.
Should stairs be poured with the slab or separately?
Separately, on their own footing below frost depth, with a bond-break or dowels to the wall. Steps poured monolithic with a stoop are fine on a small porch; anything larger cracks at the joint as the two settle differently.