Stair Calculator

Calculate stair rise, run, and stringer length while ensuring code compliance.

Stair Calculator

Calculate step rise and run for building stairs.

Total Rise (inches)

Height from lower floor to upper floor surface.

Target Rise (in)

Std max ~7.75"

Tread Run (in)

Std min ~10"

Stringer Layout

Enter dimensions to see preview

Understanding the Stair Calculator

Calculate the rise, run, and stringer length for building safe, comfortable, and code-compliant stairs. Perfect for deck builders, carpenters, and DIY home improvement.

Guide

How to use the Stair Calculator

1Measure the 'Total Rise' (vertical height from lower floor to upper floor).
2Entering a 'Target Rise' (standard is ~7.5 inches) allows us to calculate the optimal number of steps.
3Enter your 'Tread Run' (depth of the step, usually 10-11 inches).
4Review the calculated Number of Steps, Exact Rise per Step, and Stringer Length.

Applications

Common Use Cases

Deck Stairs: Building steps from a deck to the ground.

Basement Stairs: Framing stairs for a basement finish.

Porch Steps: Replacing old concrete or wooden steps.

Stringer Layout: Marking cut lines for stringers.

The Maths Behind the Calculation

Steps = TotalRise / TargetRise

We divide the total vertical height by your desired step height to find the nearest whole number of steps. We then divide the total height by this number to get the exact rise per step.

Knowledge Base

Frequently Asked Questions

What is the standard rise and run for stairs?

Building codes typically require a maximum rise of 7.75 inches and a minimum run of 10 inches. 7.5" rise and 10-11" run is a comfortable standard.

How do I calculate stringer length?

The stringer length is the hypotenuse of the right triangle formed by the total rise and total run of the stairs.

What is headroom?

Headroom is the vertical distance from the stair nosing to the ceiling above. Codes usually require a minimum of 6 feet 8 inches.

Regional Notice: United States

"Federal tax estimates are based on 2024 brackets. Consult a tax professional for official filing."

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