Roof pitch calculator
Enter a rise and a run, or an angle in degrees. This roof pitch calculator gives you the slope as x/12 and the pitch factor.
Pitch
Enter a rise to see the pitch.
- Pitch
- —
- Angle
- —
- Pitch factor
- —
Low-slope roofs (below about 3/12) usually need different materials than shingles. Check the manufacturer's requirements.
Common pitches
| Pitch | Degrees | Pitch factor |
|---|---|---|
| 0/12 | 0.0° | 1.000 |
| 1/12 | 4.8° | 1.003 |
| 2/12 | 9.5° | 1.014 |
| 3/12 | 14.0° | 1.031 |
| 4/12 | 18.4° | 1.054 |
| 5/12 | 22.6° | 1.083 |
| 6/12 | 26.6° | 1.118 |
| 7/12 | 30.3° | 1.158 |
| 8/12 | 33.7° | 1.202 |
| 9/12 | 36.9° | 1.250 |
| 10/12 | 39.8° | 1.302 |
| 12/12 | 45.0° | 1.414 |
| 14/12 | 49.4° | 1.537 |
| 16/12 | 53.1° | 1.667 |
| 18/12 | 56.3° | 1.803 |
Common questions
What is roof pitch?
Roof pitch is the steepness of the roof. It is the rise over a 12-inch run. A 6/12 pitch rises 6 inches for every 12 inches of horizontal run. A 0/12 pitch is flat.
How do I convert a pitch like 6/12 to degrees?
Divide the rise by the run. The angle of that slope is the pitch in degrees. A 6/12 pitch is 26.6 degrees. This calculator also turns an angle in degrees back into a pitch written as x/12.
How do I measure roof pitch?
Set a level so it runs 12 inches horizontally along the slope. Measure the vertical rise from the roof surface up to the level. That rise over 12 is the pitch. A 6-inch rise on a 12-inch level is a 6/12 pitch.
What counts as a low-slope roof?
A roof below about 3/12 is a low-slope roof. Low-slope roofs usually need different materials than shingles. Check the manufacturer's requirements.
What is a pitch factor and why does it matter?
The pitch factor is the square root of 1 plus (rise divided by 12) squared. A 0/12 roof has a factor of 1.000. A 6/12 roof has a factor of 1.118. Multiply the footprint by the factor to get the roof area. A steeper roof has more surface than the footprint under it.