About

Stair Rise Calc is run by one person who builds stairs for their own house and got tired of dividing a total rise by hand. Every figure on this site is computed from the measurement you type in, by the formulas printed on the pages themselves: riser count, riser height, tread run, total run, the diagonal of one step, the length the marks occupy along the board, and the board that takes them.

Nothing here is sold, nothing is recommended for a commission, and no form on this site collects a lead. The code limits come from two published sources, are stored as numbers and are shown with the document and the date they were read from; no code text is reproduced.

This site is not a contractor, not an engineer and not a code authority. It states what the arithmetic gives and what two published codes allow. What may be built where you live is your building official's to say.