Formula
How this estimate works
degrees = arctan(pitch / 12)
A 6:12 roof pitch converts to about 26.57 degrees.
Convert pitch to degrees
Pitch describes rise over run, while degrees describe the roof angle. The calculator converts pitch to angle using arctangent.
Common pitch conversions
A 4:12 roof is about 18.43 degrees, 6:12 is about 26.57 degrees, and 12:12 is 45 degrees. These conversions are useful when comparing roofing requirements written in different formats.
Assumptions used
- Pitch is shown as inches of rise per 12 inches of horizontal run.
- Rafter length uses the same units entered for rise and run.
- Pitch multiplier estimates sloped surface area from flat footprint area.
Before you order materials
- Enter the rise value from the pitch ratio, such as 6 for 6:12.
- Use angle mode when converting degrees back to pitch.
- Check low-slope material requirements separately.
Frequently asked questions
Is 6:12 roof pitch 45 degrees?
No. A 6:12 pitch is about 26.57 degrees. A 12:12 pitch is 45 degrees.
Why do roofers use pitch instead of degrees?
Pitch is easy to measure on a framing square and is common in U.S. roofing and construction.
Can I enter an angle instead?
Yes. Choose angle mode to convert degrees back into pitch and slope percentage.