Roof Pitch Calculator

Slope, Angle & Rise/Run Conversion

The Roof Pitch Calculator converts a roof rise and run measurement into the standard X-in-12 pitch ratio, the angle in degrees, and the slope multiplier used to convert flat footprint area to actual sloped surface area. Pitch directly affects how much shingle and underlayment material you need, what waste factor to apply, whether you can walk the roof safely, and which materials are even allowed by code. Use this tool together with our Roof Area Calculator and Pitch Chart to size every other material on your roof.