HOW IT IS CALCULATED
Calculate roof pitch from rise and run
Convert rise divided by horizontal run into angle, slope percentage and rise-per-12.
Instant resultClear formulaRuns locally
01Values
02pitch = atan(rise ÷ run)
03Result
4 rise over 12 run ≈ 18.43°
Degrees and percent slope describe the same geometry differently
They should not be treated as numerically interchangeable values.
02
In short
What logic does the calculator use?
pitch = atan(rise ÷ run)
Example?
4 rise over 12 run ≈ 18.43°