Concrete Steps Calculator
Estimate concrete for exterior steps from the rise, tread, width and slab thickness; see the computed riser height.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
This volume estimate models stacked concrete treads and rounds the step count up, then shows the resulting riser height. Its basic reference checks an actual riser no higher than 7.75 inches and a tread at least 10 inches, drawing on one residential-code model. It does not establish compliance with local rules or cover foundations and reinforcement; confirm a real design with the local authority or a qualified professional.
Worked example
calculated with the default values below
Total rise from ground to landing 36 in · Riser height 7 in · Tread depth 12 in · Step width 4 ft · Slab thickness 6 in Number of steps 6 · Actual riser height 6.0 in · Total depth of the staircase 60.0 in · Concrete volume 1.556 cu yd · Basic dimension reference Meets the calculator reference
General background references
Disclaimer
These calculators provide planning estimates only. Building codes, wiring regulations and safety requirements differ by country and change over time, and nothing here replaces a licensed professional or a permit. For structural, electrical or gas work, follow local code and have the installation inspected.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
s = ⌈R ÷ h⌉; V = w × d ÷ 12 × t × Σ i (i = 1…s)
- R
- total rise in inches
- h
- riser height in inches
- s
- number of steps
- d
- tread depth in inches
- w
- width in ft
- t
- slab thickness in inches
- V
- concrete volume in ft³
The tool rounds the step count up, computes actualRiser = totalRise ÷ steps, and estimates total run as (steps − 1) × tread depth. Its illustrative dimension check uses actual riser ≤ 7.75 in and tread depth ≥ 10 in; local rules may differ.
Frequently asked questions
How does the tool check riser height?
The calculator rounds the number of steps up, calculates the resulting riser height, and uses that height—not the requested target—in its basic reference check. With a 36-inch rise and a 7-inch target it returns 6 steps at 6 inches per riser. Total run uses one fewer tread than risers. The check is only an estimate; confirm the applicable local requirements for a real build.