Convert a roof pitch between the builder shorthand and the actual angle so you can order materials and cut rafters correctly. Enter the rise in inches over a standard twelve inch run, or enter both rise and run directly, and the calculator returns the pitch as an x in twelve ratio, the slope angle in degrees, and the rafter multiplier used to find true rafter length. That multiplier is the length of sloped roof per unit of horizontal run, so multiplying it by half the building width gives a rafter length before overhang. Common residential pitches range from a gentle four in twelve to a steep twelve in twelve, and the tool handles any value you enter. Knowing the angle also helps pick shingles rated for your slope. Everything is calculated instantly in your browser with no data sent anywhere.
Roof pitch is the rise over run, often written as inches of rise per 12 inches of run, such as 6 in 12.
It takes the inverse tangent of rise divided by run to convert the pitch to an angle in degrees.
It is the factor that converts horizontal run into sloped rafter length, equal to the square root of rise squared plus run squared over the run.
Convert a roof pitch between the builder shorthand and the actual angle so you can order materials and cut rafters correctly. Enter the rise in inches over a standard twelve inch run, or enter both rise and run directly, and the calculator returns the pitch as an x in twelve ratio, the slope angle in degrees, and the rafter multiplier used to find true rafter length.
Yes. Roof Pitch Calculator is completely free, with no sign-up and no usage limits.
Yes. Roof Pitch Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Roof Pitch Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.