Design code-compliant stairs by entering the total rise (floor-to-floor height). This calculator determines the optimal number of steps, riser height, tread depth, and stringer length. Results follow standard building code requirements for safe, comfortable stairs.
Enter Your Measurements
Results
Number of Risers
14
risers
Actual Riser Height
7.71
inches
Number of Treads
13
treads
Total Run
130.0
inches
Stringer Length
169.0
inches
Stair Angle
39.7
degrees
Formula
How to Use This Calculator
How to Use
- 1
Measure the total rise from the finished floor at the bottom to the finished floor at the top in inches.
- 2
Enter the desired riser height (7 to 7.75 inches per building code).
- 3
Enter the tread depth (10 to 11 inches is standard for comfortable stairs).
- 4
Enter the stair width (36 inches minimum per code for residential).
Frequently Asked Questions
Frequently Asked Questions
What is the building code for stairs?
How do I calculate stair rise and run?
What is the ideal stair angle?
In-Depth Guides
Stair Building Guide: Rise, Run, Stringer Length & Codes
Calculate stair rise, run, stringer length, and number of steps. Includes building code requirements for residential stairs and deck stairs.
Framing Lumber Guide: Sizes, Grades, and Choosing the Right Lumber
How framing lumber is sized and graded, nominal vs. actual dimensions, common lumber grades for structural use, and how to choose lumber for specific framing applications.
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About This Calculator
This calculator uses the formula: Risers = Total Rise ÷ Desired Rise (rounded) | Actual Rise = Total Rise ÷ Risers | Treads = Risers - 1 | Stringer = √(Total Rise² + Total Run²). All calculations follow industry-standard methods. Results are estimates — always verify with a licensed professional for structural or code-compliant work.
Built and maintained by the CalcSmart team. Last updated March 2026.
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