Concrete Steps Calculator: Yards and Bags for Stairs
Three concrete steps 4 ft wide with 7 in risers and 11 in treads need 12.83 cubic feet, which is 24 bags of 80 lb mix with 10% extra.
Advanced options: waste, prices
NRMCA advises ordering 4 to 10 percent over the estimate.
Concrete needed (with 10% extra)
0.52 yd³
0.40 m³ · 12.83 ft³ before extra
Steps: 4 ft × 7 in × 11 in × 0 ft. Small pour: premix bags make sense.
Premix bags
- 80 lb24
- 60 lb32
- 50 lb38
- 40 lb48
- Ready-mix cost
- $84
- Weight
- 1,925 lb
Full breakdown
| Volume before extra | 0.48 yd³ · 0.36 m³ |
|---|---|
| With 10% extra | 0.52 yd³ |
| Weight (150 lb/ft³) | 1,925 lb · 0.96 tons |
| Pallets of 40 lb (80 bags each) | 1 |
| Pallets of 60 lb (56 bags each) | 1 |
| Pallets of 80 lb (42 bags each) | 1 |
| Truckloads at 12 yd³ | 1 |
| Truckloads at 8 yd³ | 1 |
Bag counts round up, as Quikrete's own calculator does. Cost uses your prices; delivery and short-load fees are extra.
Key takeaways
- Three steps 4 ft wide take 24 bags of 80 lb mix.
- Risers max 7¾ in, treads min 10 in (IRC R311.7.5).
- Stairs must be at least 36 in wide (IRC R311.7.1).
- A top landing often needs more concrete than the steps.
How Much Concrete Do I Need for Steps?
You need the volume of every step block stacked on the ground. Three steps 4 ft wide with 7 in risers and 11 in treads hold 12.83 ft³, or 0.48 yd³ (0.36 m³). With 10% extra, that is 24 bags of 80 lb concrete.
The calculator assumes solid steps poured on grade; a sloped stair slab with a thinner throat uses less concrete.
Concrete Steps Formula
ft³ = Width (ft) × (Tread (in) ÷ 12) × (Riser (in) ÷ 12) × n × (n + 1) ÷ 2
Landing: + Width × Landing depth (ft) × total rise (ft)Each step is a solid block from the ground up, so step 1 is one riser tall, step 2 is two risers, and so on.
How Many Bags of Concrete for Steps?
Bags for solid concrete steps (7 in riser, 11 in tread, 4 ft wide), with 10% extra, are listed by step count.
| Project | yd³ with 10% | 80 lb bags | 60 lb bags | 50 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 2 steps, 4 ft wide | 0.26 | 12 | 16 | 19 | 24 |
| 3 steps, 4 ft wide | 0.52 | 24 | 32 | 38 | 48 |
| 4 steps, 4 ft wide | 0.87 | 40 | 53 | 63 | 79 |
How Many Concrete Steps Do I Need?
You need the total rise divided by the riser height, rounded up. Risers may not exceed 7¾ in (196 mm) and treads must be at least 10 in (254 mm) under the 2021 IRC (R311.7.5). A 21 in rise gives 21 ÷ 7.75 = 2.7, so 3 steps of 7 in.
How Many Steps for a 24 Inch Rise?
A 24 in rise needs 4 steps: 24 ÷ 7.75 = 3.1, which rounds up to 4 steps of 6 in each.
How Wide Should Concrete Steps Be?
Stairways must be at least 36 in (914 mm) wide in clear width under the 2021 IRC (R311.7.1). Most entry steps are 4 ft wide, the calculator's default.
Concrete Steps With a Landing
A landing at the top adds its width × depth × total rise. Three steps with a 4 ft deep landing add 4 × 4 × 1.75 = 28 ft³, so the landing usually needs more concrete than the steps.
Bags or Ready-Mix for Steps?
Bags suit two to four steps, and ready-mix suits steps with a landing above about 1 yd³, which is this calculator's own rule.
How Much Do Concrete Steps Cost?
The concrete for three steps costs 24 bags × your bag price. Forms and finishing add most of the labor; precast steps are an alternative sold by the unit.
What PSI Concrete for Outdoor Steps?
Outdoor steps need 2,500, 3,000 or 3,500 psi concrete in negligible, moderate and severe weathering regions, under 2021 IRC Table R402.2.
Worked Examples: Two, Four and Landing Steps
Two steps, 4 ft wide, 7 in risers, 11 in treads. 6.42 ft³; with 10% extra, 12 bags of 80 lb mix.
Four steps, 5 ft wide, 7 in risers, 11 in treads. 26.74 ft³; with 10% extra, 50 bags, or 1.09 yd³.
Three steps plus a 4 ft landing, 4 ft wide. 40.83 ft³; with 10% extra, 1.66 yd³, a job for ready-mix.
How to Measure for Concrete Steps
- Measure the total rise from the ground to the door threshold.
- Divide by 7¾ in or less to get the number of steps (IRC R311.7.5.1).
- Choose a tread of at least 10 in (IRC R311.7.5.2).
- Measure the width; stairs must be at least 36 in (IRC R311.7.1).
How Much Do Concrete Steps Weigh?
Three solid steps 4 ft wide weigh about 1,925 lb at 150 lb/ft³, so poured-in-place steps are rarely moved once set.
Concrete Steps Calculator FAQ
How many bags of concrete for 2 steps?
Two steps 4 ft wide with 7 in risers and 11 in treads take 12 bags of 80 lb concrete or 16 bags of 60 lb, with 10% extra.
How do I figure out how many concrete steps I need?
Divide the total rise by the riser height, at most 7¾ in under IRC R311.7.5.1, and round up; a 21 in rise needs 3 steps of 7 in.
What is the formula for calculating steps?
Concrete volume = width × tread × riser × n × (n + 1) ÷ 2 for n solid steps, all in feet.
Next step
Check the rise with your door height, then pick the right strength for outdoor steps in the concrete psi by project.
Official sources
Last reviewed 2026-11-05. Numbers come from our tested engine; see how we calculate and our sources.