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Roof Pitch Calculator

Calculate roof pitch as X:12, angle in degrees, slope percentage, and the roof area multiplier. Enter rise and run measurements or a pitch ratio to get instant results.

Results

Pitch

6.0:12

Angle

26.6°

Slope

50.0%

Area Multiplier

1.118

Common Pitch Factor Table

PitchAngleSlope %Area Multiplier
1:124.8°8.3%1.003
2:129.5°16.7%1.014
3:1214.0°25.0%1.031
4:1218.4°33.3%1.054
5:1222.6°41.7%1.083
6:1226.6°50.0%1.118
7:1230.3°58.3%1.158
8:1233.7°66.7%1.202
9:1236.9°75.0%1.25
10:1239.8°83.3%1.302
11:1242.5°91.7%1.357
12:1245.0°100.0%1.414
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How to Use This Calculator

Select your input mode: enter a rise and run in inches, or enter a pitch ratio directly (the rise per 12 inches of run). The calculator outputs the pitch in X:12 format, the angle in degrees, slope as a percentage, and the roof area multiplier (used to convert flat area to actual roof area). Scroll down for a handy reference table of common pitches.

Formula Used

Pitch = (Rise / Run) x 12. Angle = arctan(Rise / Run) in degrees. Slope % = (Rise / Run) x 100. Area Multiplier = sqrt(1 + (Rise / Run)^2).

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Disclaimer

This calculator is for estimation purposes only. Results may vary based on local conditions, materials, and building codes. Always consult a licensed professional before making decisions based on these calculations. MyContractorTools is not responsible for any errors or omissions.