METHOD
Formula and method
Riser count rounds up; treads = risers−1 because the upper floor forms the final landing.
Stair dimensions for a straight staircase with equal risers
Lay out equal risers for a simple straight staircase.
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Your inputs
Starting values are an example. Replace them with your own.
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02
Your result
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About this result
Informational calculations. Check assumptions, dates and jurisdiction before making a decision.
Full disclaimerHow do you work out the number of steps?
The calculator divides the total finished floor to floor height by your target riser height and rounds the riser count up, so all risers are equal and slightly lower than the target. There is one fewer tread than risers, because the upper floor forms the last step. From the tread depth and stair width you get the horizontal run and tread area. For example, a 108 inch rise with a 7 inch target gives 16 risers of 6.75 inches and 15 treads. It does not check building code compliance.
TRACEABLE
Sources and validity
Basic arithmetic or geometry using the formula shown. Uses only your inputs.
How we maintain data