Roof Pitch Calculator
LIVE RESULTStandard run = 12 in
Your Results
PITCH · ANGLE · SLOPEConventional / standard slope
Drag the orange apex to change both rise and run, or the blue handles to adjust one at a time. The boxes above stay in sync.
Pitch ↔ Degrees · Two-Way
Roof Pitch to Degrees Calculator & Chart
Convert any roof pitch to degrees — and back again. Enter rise and run on the right for the angle in degrees instantly, use the quick degrees → pitch converter below, or read the full conversion chart.
- Angle in degrees = arctan(rise ÷ run)
- Two-way: pitch → degrees and degrees → pitch
- Full roof-pitch-to-degrees chart included
- Switch between inches and millimetres
How to Convert Roof Pitch to Degrees
Roof pitch is written as rise over run, such as 6:12. The angle in degrees is the arctangent of rise divided by run:
angle° = arctan(rise ÷ run)
A 6:12 pitch is arctan(6 ÷ 12) = 26.57°. A 12:12 pitch is arctan(1) = 45°. You do not need a separate roof angle calculator — the tool above shows the angle the moment you type.
Degrees to Roof Pitch Converter
Know the angle but need the pitch? Enter an angle in degrees to get the equivalent pitch as an X:12 ratio, the slope percentage and the multiplier.
Roof Pitch to Degrees Chart
Every common pitch with its angle in degrees, slope percentage and multiplier.
| Roof pitch | Angle (degrees) | Slope (%) | Multiplier |
|---|---|---|---|
| 0.5:12 | 2.39° | 4.2% | 1.0009 |
| 1:12 | 4.76° | 8.3% | 1.0035 |
| 1.5:12 | 7.13° | 12.5% | 1.0078 |
| 2:12 | 9.46° | 16.7% | 1.0138 |
| 2.5:12 | 11.77° | 20.8% | 1.0215 |
| 3:12 | 14.04° | 25.0% | 1.0308 |
| 3.5:12 | 16.26° | 29.2% | 1.0417 |
| 4:12 | 18.43° | 33.3% | 1.0541 |
| 4.5:12 | 20.56° | 37.5% | 1.0680 |
| 5:12 | 22.62° | 41.7% | 1.0833 |
| 5.5:12 | 24.62° | 45.8% | 1.1000 |
| 6:12 | 26.57° | 50.0% | 1.1180 |
| 6.5:12 | 28.44° | 54.2% | 1.1373 |
| 7:12 | 30.26° | 58.3% | 1.1577 |
| 7.5:12 | 32.01° | 62.5% | 1.1792 |
| 8:12 | 33.69° | 66.7% | 1.2019 |
| 8.5:12 | 35.31° | 70.8% | 1.2255 |
| 9:12 | 36.87° | 75.0% | 1.2500 |
| 9.5:12 | 38.37° | 79.2% | 1.2754 |
| 10:12 | 39.81° | 83.3% | 1.3017 |
| 10.5:12 | 41.19° | 87.5% | 1.3288 |
| 11:12 | 42.51° | 91.7% | 1.3566 |
| 11.5:12 | 43.78° | 95.8% | 1.3851 |
| 12:12 | 45.00° | 100.0% | 1.4142 |
Degrees to Roof Pitch Chart
Starting from a known angle instead? These are the most common roof angles and their equivalent pitch.
| Angle (degrees) | Roof pitch | Slope (%) | Multiplier |
|---|---|---|---|
| 5° | 1.05:12 | 8.7% | 1.0038 |
| 10° | 2.12:12 | 17.6% | 1.0154 |
| 15° | 3.22:12 | 26.8% | 1.0353 |
| 17.5° | 3.78:12 | 31.5% | 1.0485 |
| 20° | 4.37:12 | 36.4% | 1.0642 |
| 22.5° | 4.97:12 | 41.4% | 1.0824 |
| 25° | 5.60:12 | 46.6% | 1.1034 |
| 26.57° | 6.00:12 | 50.0% | 1.1181 |
| 30° | 6.93:12 | 57.7% | 1.1547 |
| 33.69° | 8.00:12 | 66.7% | 1.2018 |
| 35° | 8.40:12 | 70.0% | 1.2208 |
| 40° | 10.07:12 | 83.9% | 1.3054 |
| 45° | 12.00:12 | 100.0% | 1.4142 |
Frequently Asked Questions
What is a 6/12 roof pitch in degrees?
A 6:12 roof pitch equals about 26.57 degrees, found from arctan(6 divided by 12).
How do I convert degrees to roof pitch?
Multiply the tangent of the angle by 12 to get the rise per 12 of run. For example, tan(30 degrees) times 12 is about 6.93, so 30 degrees is roughly a 6.93:12 pitch.
What roof pitch is 45 degrees?
A 45 degree roof is a 12:12 pitch, because the rise equals the run.
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