Stair Calculator
Calculate stair riser count tread depth total run and code-friendly stair dimensions.
Risers ≤ 7¾", treads ≥ 10". Rise+Run rule: 17-18.
About this tool
Stair Calculator is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.
Category: Trade & Construction Calculators. Browse more Trade & Construction Calculators tools.