Stair Calculator
Estimate stair riser count, riser height, tread count, and total run.
How this calculator works
How to use this calculator
Enter the project measurements and material details requested in the calculator. Then click Calculate to estimate the result. For best accuracy, measure carefully and update any default material values based on your supplier or project plan.
Formula used
Number of Risers = Total Rise ÷ Target Riser Height, rounded to nearest whole number. Actual Riser Height = Total Rise ÷ Number of Risers. Total Run = Number of Treads × Tread Depth.
Example calculation
For a 108 inch total rise, 7.5 inch target riser, and 10 inch tread depth, the estimate is 14 risers, 13 treads, and 130 inches of total run.
What the result means
The result provides a planning estimate for stair layout. Always check local building codes before construction.
Frequently asked questions
Should I check building codes?
Yes. Stair dimensions are safety-sensitive and must follow local rules.