Roof Pitch to Degrees Calculator

Pitch, Degrees, Percent Grade and Area Multiplier

Roof pitch and roof angle describe the same steepness in two different languages, and this calculator translates freely between them. Enter a pitch as rise in inches per 12 inches of run and you get the angle in degrees, the percent grade, the area multiplier that converts a flat footprint into true sloped surface, the hip and valley multiplier for diagonal members, and the radian value. Enter an angle instead and it works backwards to the nearest standard rise over 12. Degrees come from the arctangent of rise divided by twelve, which is why a 12:12 roof is exactly 45 degrees and a 6:12 roof is 26.57 degrees. Add your footprint area and the tool also returns the sloped roof area in square feet and roofing squares, so you can order material from a ground measurement. The page includes a full pitch to degrees conversion chart from 1:12 to 18:12 and the minimum slope requirements for shingles, metal, tile and membrane roofing.