Primary material
62 bags
80 lb concrete mix
Use the calculated bag count as your buying starting point, then verify yield and pallet limits with the store.
Concrete stairs calculator
Concrete stairs calculator for porch and entry steps.
Enter step count, rise, run, width, and waste allowance to estimate cubic yards, bag count, and rough material cost for uniform concrete steps.
3 steps, 7 in x 11 in x 4 ft
0.52 yd³
24 bags at 80 lb
Formula
R x D x W x N(N+1)/2
Solid pour, rise/run in feet
Best for
Uniform steps
Porch, entry, simple exterior stairs
Quick stairs answers
Common stair layouts
3 porch steps
3 steps x 7 in rise x 11 in run x 4 ft wide
0.52 yd³
24 bags at 80 lb with default 10% waste
5 entry steps
5 steps x 7 in rise x 11 in run x 5 ft wide
1.63 yd³
74 bags at 80 lb with default 10% waste
6 wide steps
6 steps x 7.5 in rise x 12 in run x 6 ft wide
3.21 yd³
145 bags at 80 lb with default 10% waste
Landings and complex forms
Estimate landings as slabs and add them to the stair volume. Curved or hollow stair forms need a separate project takeoff.
Shopping list
Ready to price and order
Use the calculated quantities as a starting cart, then compare store availability, delivery fees, pallet limits, and local ready-mix minimums before buying.
Large pours
Ready-mix quote check
For high bag counts, compare the bagged route against local ready-mix minimums, delivery, access, and unload time.
Optional base
Gravel base
Base depth is project-specific. Estimate it separately before adding bags or bulk gravel to the order.
Optional forms
Forms and stakes
Plan lumber, stakes, screws, release, and bracing around the perimeter and any step-downs or curves.
Store buttons open retailer search results for now. Confirm exact product yield, pickup, delivery, and pallet rules before ordering.
Formula shown
How the stairs calculation works
1. Convert rise and run to feet
rise ft = rise in / 12; run ft = run in / 12
2. Stack the steps into a solid wedge
cubic feet = rise ft x run ft x width ft x N(N+1)/2
Each step also supports every step above it, so the volume is not just N equal blocks.
3. Add waste and estimate bags
bags = ceil(cubic feet x (1 + waste) / bag yield)
Solid pour vs. filled core
This estimate assumes a fully solid pour. Many exterior steps are built over a compacted gravel or fill core with only a concrete shell, which uses noticeably less concrete — estimate that shell separately. Landings, sidewalls, nosing, thickened bottom steps, flared sides, and hollow forms should also be estimated on their own. Code-compliant stair geometry and reinforcement are outside this material estimate.
Sources
- Quikrete product yields — bagged concrete mix yield references
- Sakrete bagged concrete references — common bag sizes and concrete mix guidance
- ConcreteNetwork concrete price guide — ready-mix and installed concrete cost context
Reviewed for estimating accuracy
Last updated: June 20, 2026
Estimate only.
This calculator is not a quote. Verify product yield, price, delivery minimums, and local conditions with your supplier or contractor before buying materials.
Related calculators
Other concrete tools
Concrete slab Use for landings, patios, shed pads, sidewalks, and driveway panels. Concrete footing Use for footings below stair supports, walls, and piers. Concrete calculators Browse all concrete shapes and cost tools. Deck stair & stringer Building wood stairs instead? Size risers, treads, and stringers.
FAQ
Concrete stairs questions
Answers for step volume, landings, irregular forms, and material-estimate limitations.
How do I calculate concrete for stairs? + -
A solid poured staircase is a stepped wedge, because each step also supports the steps above it. Multiply rise in feet by run in feet by stair width in feet by N(N+1)/2 (that is 1 + 2 + ... + N for N steps), then add the entered waste allowance. To pour less, fill the stair core with compacted gravel and estimate only the concrete shell.
How much concrete is needed for 3 porch steps? + -
For 3 solid steps with a 7 inch rise, 11 inch run, and 4 ft width, the calculator estimates about 0.52 cubic yards with the default 10% waste, or about 24 bags of 80 lb concrete mix. That assumes a solid pour; filling the core with compacted gravel uses less. You can edit waste for your forms and jobsite conditions.
Does this work for stairs with a landing? + -
Estimate the steps and landing separately, then add them together. A landing is usually calculated more like a small slab.
Can this estimate curved or irregular stairs? + -
No. This version assumes uniform rectangular steps. Curved, flared, hollow, or irregular stair forms need a project-specific takeoff.
Is this stairs estimate a structural design? + -
No. It estimates concrete quantity and rough material cost only. Stair geometry, reinforcement, footing, nosing, code dimensions, and handrail requirements should be verified before pouring.