Donaldson R F Stair Calculator
Enter the total height from finished floor to finished floor and get equal steps, with the pitch and a check against the UK Building Regulations limits.
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Rise, going and pitch
The rise is the height of each step, the going is the depth of each tread (measured from the front edge of one nosing to the next) and the pitch is the angle of the stair. A flight starting and ending at floor level has one more riser than treads, because the top floor acts as the last tread. All steps in a flight must be equal.
In England (Approved Document K), a private stair can have a rise up to 220 mm, a going of at least 220 mm and a pitch up to 42°. Institutional and assembly buildings allow at most 180 mm rise and need 280 mm going with 38°; other buildings allow 190 mm and 250 mm with 38°. A comfortable stair also satisfies 550 mm ≤ 2 × rise + going ≤ 700 mm. Minimum headroom is 2.0 m.