Stairs Calculators
Stairs are pure geometry: total rise divided into equal, comfortable risers, with tread depth to match. This calculator works out riser count, individual riser height, tread depth, and total run from your floor-to-floor height. Stair codes are strict and vary by jurisdiction — use this for planning and layout, then verify every dimension against your local requirements.
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Stairs FAQs
Residential codes commonly cap risers around 7¾ inches with treads near 10–11 inches deep, though limits vary by jurisdiction. The calculator targets even risers in a comfortable range — always confirm against your local code before building.
Measure vertically from the finished floor below to the finished floor above — finished surfaces, not subfloor. Even a 3/8-inch flooring change alters every riser, so measure what the stairs will actually land on.
Estimates are planning guides, not professional advice. Read the disclaimer.