Stair Calculator
Calculate the number of steps, actual riser height, total run, and stringer length for your staircase. Includes a text-based stair diagram.
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Results
Number of Steps
15
Actual Riser Height
7.20 inches
Total Run
150.0 inches
Stringer Length
184.8 inches
Stair Diagram
┌──────┐ │ step 1 │ ┌──────┐ │ step 2 │ ┌──────┐ │ step 3 │ ┌──────┐ │ step 4 │ ┌──────┐ │ step 5 │ ┌──────┐ │ step 6 │ ┌──────┐ │ step 7 │ ┌──────┐ │ step 8 │ ┌──────┐ │ step 9 │ ┌──────┐ │ step 10 │ ┌──────┐ │ step 11 │ ┌──────┐ │ step 12 │ ┌──────┐ │ step 13 │ ┌──────┐ │ step 14 │ ┌──────┐ │ step 15 │ └──────┘How is a Staircase Calculated?
A stair calculator determines the number of steps, actual riser height, total run, and stringer length for your staircase. It ensures your stairs meet building codes and are comfortable to use.
Actual Riser = Total Rise / Steps
Total Run = Steps × Tread Depth
Stringer Length = √(Rise² + Run²)
Example
For a 108-inch rise with 7.5-inch risers and 10-inch treads, you need 15 steps with an actual riser of 7.2 inches. The total run is 150 inches and the stringer length is about 184 inches (15.3 feet).
Common Use Cases
- Planning a home renovation or new staircase build.
- Ensuring compliance with local building codes (typical riser: 7–7.75 inches).
- Calculating materials needed for stringers, treads, and risers.
FAQs
What is the standard riser height?
Most building codes require risers between 4 and 7.75 inches, with 7 to 7.5 inches being the most comfortable and common range for residential stairs.
What is a stringer?
A stringer is the structural support member that runs along the side of the staircase, cut to hold the treads and risers. Its length determines the diagonal span of your stairs.