Enter the roof’s rise and run to get its pitch in the standard x/12 format, the angle in degrees, and the slope as a percentage. Roofers, framers, and DIYers use pitch for everything from rafter cuts to shingle orders.
How to use this calculator
- Measure the rise (vertical height) and the run (horizontal distance) in inches.
- The tool converts them to pitch (x/12), roof angle, and slope grade instantly.
- Tip: hold a 12-inch level horizontally against the roof and measure straight down to the surface — that drop is your x in x/12.
The math behind it
Pitch = rise ÷ run × 12, expressed as x/12. Angle = arctan(rise ÷ run), converted to degrees. Slope grade = rise ÷ run × 100%. A 6-inch rise over a 12-inch run is a 6/12 pitch, about 26.6°.
FAQs
What is a 6/12 roof pitch?
It means the roof rises 6 inches for every 12 inches of horizontal run — roughly a 26.6° angle. It’s one of the most common residential pitches.
What pitch is walkable?
Most pros consider 7/12 and below walkable with care; anything steeper needs fall protection and staging.
Why does pitch matter for materials?
Steeper roofs have more surface area than the footprint suggests, need different underlayment, and cost more in labor. Use your pitch with our roof shingle calculator for a full material estimate.
Related calculators
- Rafter calculator — rafter lengths from span and pitch
- Roof shingle calculator — bundles and squares
- Square footage calculator