Stair Calculator
Design your staircase — calculate steps, risers, treads, and angle.
Stair Dimensions
What is the Stair Calculator?
The Stair Calculator is a construction tool designed for carpenters, builders, and DIYers. It calculates the exact number of steps, rise, and run required to build a safe, building-code-compliant staircase between two elevations.
How It Works (Formula)
The algorithm divides the total vertical height (Total Rise) by the standard ideal step height (usually around 7 inches) to determine the number of steps. It then adjusts the math to ensure every single step is exactly the same height, which is a strict requirement for building safety.
$$ \text{Rise Per Step} = \frac{\text{Total Rise}}{\text{Number of Steps}} $$
Building codes generally dictate a maximum rise of 7.75 inches.
How to Use It
Measure the total vertical distance from the bottom floor to the top floor. Enter this "Total Rise" into the calculator. The tool will output the optimal number of stairs, the exact height of each riser, and the depth of each tread.