Stair Calculator
Result
Stair Calculator — free online calculator.
Formula
- Stair Calculator calculates its result from Total Rise (Height), Riser Height, Tread Depth (Going), Stair Width. It uses the formula Steps = ceil(Rise / Riser Height); Total Run = Steps × Tread; Stringer = √(Rise² + Run²). Change any input to recalculate the result instantly.
- The main inputs are Total Rise, Riser Height, Tread Depth, Stair Width. Enter them in the units and format shown in the calculator.
- Keep measurements and project assumptions consistent before comparing or combining values.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Stair
- Total Rise: 3 Height
- Riser Height: 0.18
- Tread Depth: 0.25 Going
- Stair Width: 1
Rise 3m with intended 0.18m riser gives 17 steps, actual riser 176.47mm, run 4.25m and stringer about 5.20m.
Sample result: Calculating…
Frequently asked questions
What does the Stair calculate?
Stair Calculator — free online calculator.
Which values should I enter?
Enter Total Rise, Riser Height, Tread Depth, Stair Width using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: Steps = ceil(Rise / Riser Height); Total Run = Steps × Tread; Stringer = √(Rise² + Run²).
Why might my result differ from another source?
Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.