Stairs
Concrete Step Calculator
Solid stairs are a stack of rectangles, each one a step taller than the one above it. The tool adds that stack.
Your region
Feet, inches, cubic yards, and 40–80 lb bags
Concrete Calculator
Example measurements — replace them with yours.
Common sizes
Most orders add 5–10% for spillage, uneven ground, and the last bit left in the chute.
Cost, truck size, and concrete weight
Leave a price blank to skip that estimate. Use the number your supplier quoted.
This job
Add each pour — slab, piers, steps — and Concrete Calculator totals them.
How to use a concrete step calculator
Solid stairs are a stack of rectangles. The bottom step is one riser tall, the next two, and so on. Volume = width × tread × riser × n(n+1)/2. A thin waist slab with open space under it uses less — do not use the solid formula for that shape.
The comfort check 2×riser + tread near 24–26 inches is a proportion hint. Local code sets maximum riser and minimum tread. Landings are separate slabs — run the slab calculator for the pad at the top or bottom.
Worked example: 4 ft wide, 4 steps, 11 in tread, 7 in riser
Width × tread × riser × 10 = 3 × (11/12) × (7/12) × 10 ≈ 16.0 ft³ ≈ 0.59 yd³ neat. Landing is a separate slab pour. Six solid steps at the same tread/riser jump to n(n+1)/2 = 21 — more than double four steps, not 50% more. Re-run the Concrete Step Calculator after thickness changes — depth moves yardage faster than length.
Stringers vs solid pours
Wood or steel stringer stairs with thin treads are not this calculator. If you are pouring a solid stoop or monolithic stair block, stay here. If each tread is a thin cast on fill, measure the true concrete thickness instead of the full riser stack.
Common mistakes
Counting treads instead of risers.
- Using the solid formula on stringer stairs with voids.
- Forgetting the landing pad.
Bags, yards, or a truck?
Most residential stair pours are bags or a short load with the landing.
The formula Concrete Calculator uses
V = W × T × R × n(n+1)/2 for solid steps.
Who this is for
Builders pouring stoop stairs.
Remodelers replacing wood steps with solid concrete.
Concrete step calculator — counting risers
Count risers, not treads, for the solid formula. Three risers make a common short stoop; the series factor n(n+1)/2 is 6, not 3. Four risers use 10; five use 15; six use 21. Width and tread scale the whole stack linearly.
Concrete steps cost calculator searches need volume first, then your installed rate. Landings are slabs. Stringer stairs with thin treads are not solid stacks — measure the true concrete, or do not use this shape.
Landing and apron
Most stoops fail the order when the landing is forgotten. A 4×4 landing at 4 inches is 0.49 yd³ neat by itself — almost as much as a small solid stair stack. Add it on the slab calculator and sum the job.
Related calculators and guides
Open the pages that match the next question on the job — volume is only the first number.
- Slab calculator for landings
- Volume calculator
- Concrete formula guide
- Cost calculator
Frequently asked questions
How do I calculate concrete for stairs?
For solid steps, use width × tread × riser × n(n+1)/2.
Does this include the landing?
No — calculate it as a slab.
What riser and tread should I use?
Follow code and the drawing. The comfort line is only a check.
Why n(n+1)/2?
Each step adds one more riser of height to the stack above it.