🪜 Stair Calculator
Rise, run and total stairs for any height
About this calculator
Stairs must meet code: comfortable risers and proper tread depth. Enter the total rise (floor to floor) and the calculator divides it into equal riser heights within the comfortable 7–7.75 inch range, then computes the tread depth, number of steps, total run, and stringer length using the Pythagorean theorem.
Tip: in Canada, the National Building Code caps riser height at 200 mm (about 7⅞") — and keep every riser equal to the millimetre, since uneven steps are a trip hazard.