This is an easy calculator to determine the rise:

RISE: the height of one step in a staircase. This is the amount of vertical distance one moves when stepping from one stair onto the next. The rise should be between 5" & 7.5" with the ideal rise for a residence being 7".

and the run:

RUN: the horizontal distance of one stair. It is how far in, the stair goes which gives the amount of room for a persons foot. The run should be between 8.5" and 14". An intermediate run is 11". The stair tread is the RUN plus the nosing. Per most Building Codes, the tread should be between 9.5" and 14". An intermediate tread is 12".

of each step and the length of the boards needed for the stair stringers.

Numbers can be entered with a decimal or fraction (i.e. 8.0625 or 8 1/16).

1. Measure the 'total rise' (from the surface of the upper floor to the surface of the lower floor).
2. Enter this amount into Total Rise and set calculator for either inches or centimeters.
3. Select a common rise-run combination from Simple or enter your own in Custom.
4. Press the Calculate button and read the results in Exact Measurements
5. To print this page, go to the File menu at the top of the window. Then click on Print

Calculator is set for: Inches  Centimeters

Total Rise  Simple Custom length in inches 5" rise and 13" run (least steep) 6" rise and 12" run (for elderly) 7" rise and 11" run (average) 7 5/8" rise and 10 1/2" run (residential) 7 7/8" rise and 10" run (steep)
Custom: Rise Run

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