Roof Pitch Calculator
Updated Formulas shown
Pitch is the rise in inches over 12 inches of horizontal run. A 6/12 roof rises 6 in per foot — an angle of 26.6°.
Roof pitch
6/12
26.6°
- Angle
- 26.57°
- Slope
- 50%
- Area multiplier
- 1.118
- Rafter length per ft of run
- 1.118 ft
Standard slope for asphalt shingles.
Quick reference
| Pitch | Angle | Slope % | Multiplier |
|---|---|---|---|
| 1/12 | 4.8° | 8.3% | 1.003 |
| 2/12 | 9.5° | 16.7% | 1.014 |
| 3/12 | 14° | 25% | 1.031 |
| 4/12 | 18.4° | 33.3% | 1.054 |
| 5/12 | 22.6° | 41.7% | 1.083 |
| 6/12 | 26.6° | 50% | 1.118 |
| 7/12 | 30.3° | 58.3% | 1.158 |
| 8/12 | 33.7° | 66.7% | 1.202 |
| 9/12 | 36.9° | 75% | 1.25 |
| 10/12 | 39.8° | 83.3% | 1.302 |
| 11/12 | 42.5° | 91.7% | 1.357 |
| 12/12 | 45° | 100% | 1.414 |
Related calculators
- Roofing CalculatorFree roofing calculator: house dimensions and pitch to roof area, squares, shingle bundles, underlayment and installed cost.
- Stair CalculatorStair calculator: number of steps, riser height, tread run, stringer length and angle from total rise, checked against IRC code.
- Roof Square Footage CalculatorTurn your house footprint and roof pitch into actual roof square footage and roofing squares.
Frequently asked questions
What is the most common roof pitch?
Between 4/12 and 9/12 for houses; 6/12 is very common.
What angle is a 4/12 pitch?
18.4 degrees.
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