Free Stair Calculator

📐 Stair Calculator

Calculate accurate stair dimensions, rise, run, and ensure building code compliance

Enter values and click Calculate to see results

Advanced Options

Enter values and click Calculate to see results

Stair Terminology & Building Codes

Rise/Riser

The vertical distance between steps. Building codes typically recommend a maximum rise of 7.75 inches (19.7 cm) per step. Our stair calculator helps you achieve optimal rise measurements for safe, comfortable stairs.

Run/Tread

The horizontal depth of each step where your foot lands. Standard building codes suggest a minimum run of 10 inches (25.4 cm). Use our stair calculator to ensure proper tread depth for your project.

Nosing

The overhang at the edge of each tread. Building codes generally recommend nosing between 0.75 and 1.25 inches (1.9-3.2 cm). Our stair calculator accounts for nosing in total run calculations.

Headroom

The vertical clearance above stairs. Building codes require at least 6 feet 8 inches (203.2 cm) of headroom. Our stair calculator helps you verify adequate headroom for your design.

Stringer

A structural support beam for stairs. Typically, there are three in a staircase: one on each side and one in the middle. Our stair calculator offers both standard and flush mounting options.

Stair Width

Measured from edge to edge of each side of the tread, perpendicular to tread length. Building codes generally suggest stairs be at least 36 inches (91.44 cm) wide.

Frequently Asked Questions

What is a stair calculator used for?
A stair calculator computes precise stair dimensions including rise, run, tread depth, and stringer length. Our free online stair calculator ensures your stairs meet building codes and safety standards.
How accurate is this calculator?
Our stair calculator uses industry-standard formulas and building code requirements. For professional projects, always verify calculations with local building codes.
Can I use this for commercial projects?
Yes. Our comprehensive online stair calculator accommodates both residential and commercial stair designs with customizable options for headroom, mounting, and tread configurations.
Does it support metric measurements?
Absolutely. Our stair calculator supports feet, inches, meters, and centimeters, making it versatile for international projects.
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