Roof Pitch Calculator
Convert rise/run to roof pitch, angle, and slope.
Roof pitch
6.0 : 12
Moderate
Angle
26.6°
Slope
50.0%
Length factor
×1.118
Common pitches
- 3:12 → 14.0° (low slope minimum)
- 4:12 → 18.4° (most common)
- 6:12 → 26.6° (medium)
- 9:12 → 36.9° (steep)
- 12:12 → 45° (very steep)
- 2:12 → 9.5° (rolled roofing only)
Rise over run is measured per 12 inches of horizontal distance. The length factor multiplies your floor footprint to get the actual sloped roof area for shingle estimating.
About
Enter rise over run. Get the standard X:12 pitch, angle in degrees, slope as a percentage, and the length factor that multiplies floor footprint to actual sloped roof area for shingle ordering.
How to use
- Enter the rise.
- Enter the run (usually 12 inches).
- Read pitch, angle, and length factor.
FAQ
What pitch is most common?+
Most American homes are 4:12 to 6:12. Anything below 3:12 is considered a low-slope roof and needs different waterproofing.