Free calculator
Roof Pitch Calculator
Calculate roof pitch, slope angle, slope percentage and roof-area multiplier from rise and run measurements.
Your project details
Change the inputs below to match your project.
Planning tool only. Verify field measurements, material specifications and project requirements before ordering materials or starting work.
Roof pitch explained
Roof pitch describes vertical rise compared with horizontal run. A 6:12 roof rises 6 inches for every 12 inches of horizontal run.
Why pitch matters
Pitch affects roof surface area, walkability, labor difficulty and sometimes material suitability. The area multiplier can help convert horizontal footprint area into approximate sloped roof area for simple roof planes.
Use pitch in your budget
After calculating pitch, use the Roof Replacement Cost Calculator and Roofing Square Calculator.