Stair Calculator
Calculate stair dimensions, risers, treads, and stringers for construction projects. Ensure safety compliance with proper stair design calculations.
Stair Calculator
Stair Results
Enter dimensions to calculate stair design
Stair Construction Information
Stair Components
- • Riser: Vertical part of each step
- • Tread: Horizontal part of each step
- • Stringer: Support beam for the stairs
- • Handrail: Safety railing for support
- • Baluster: Vertical posts supporting handrail
Construction Tips
- • Measure Twice: Double-check all measurements
- • Level Steps: Ensure all treads are level
- • Secure Stringers: Properly attach to structure
- • Safety First: Follow local building codes
- • Professional Help: Consult experts for complex projects
About the Stair Calculator
Our free stair calculator finds rise, run, number of steps, and stringer length from total height and run or from desired step dimensions. Use it for interior and exterior stairs. Building codes often limit rise and run; check local rules. For other construction use our concrete calculator or area calculator.
You may also find our concrete calculator and area calculator useful.
Frequently Asked Questions
What is a comfortable rise and run?
Common guidelines: rise 170–200 mm, run 250–280 mm. Two × rise + run often kept around 600–640 mm. Local codes may specify limits.
How do I calculate number of steps?
Divide total rise by desired rise per step. Round to a whole number and recalculate actual rise so total height is correct.
What is stringer length?
The stringer is the diagonal support. Length = √(total run² + total rise²). This calculator gives it from your dimensions.