Choose a direction, enter a pitch or an angle, and get the other one along with the slope percentage and slope factor. The chart below lists every common pitch from 1/12 to 24/12.
Pitch ↔ degrees calculator
How it works
- Pitch to degrees: angle = arctan(pitch ÷ 12)
- Degrees to pitch: pitch = tan(angle) × 12
- Slope factor = √(1 + (pitch ÷ 12)²)
Worked example
Converting a 6/12 pitch:
- Convert: Pitch (x in 12) to degrees
- Pitch: rise per 12 in: 6 in
The calculator gives:
- Angle: 26.57°
- Slope percentage: 50.0%
- Slope factor: 1.1180
arctan(6 ÷ 12) = arctan(0.5) = 26.57°. Going the other way, 30° is tan(30°) × 12 = 6.93, just under a 7/12 pitch.
Roof pitch to degrees chart
| Pitch | Angle | Slope | Slope factor |
|---|---|---|---|
| 1/12 | 4.76° | 8.3% | 1.003 |
| 2/12 | 9.46° | 16.7% | 1.014 |
| 3/12 | 14.04° | 25.0% | 1.031 |
| 4/12 | 18.43° | 33.3% | 1.054 |
| 5/12 | 22.62° | 41.7% | 1.083 |
| 6/12 | 26.57° | 50.0% | 1.118 |
| 7/12 | 30.26° | 58.3% | 1.158 |
| 8/12 | 33.69° | 66.7% | 1.202 |
| 9/12 | 36.87° | 75.0% | 1.250 |
| 10/12 | 39.81° | 83.3% | 1.302 |
| 11/12 | 42.51° | 91.7% | 1.357 |
| 12/12 | 45.00° | 100.0% | 1.414 |
| 14/12 | 49.40° | 116.7% | 1.537 |
| 16/12 | 53.13° | 133.3% | 1.667 |
| 18/12 | 56.31° | 150.0% | 1.803 |
| 20/12 | 59.04° | 166.7% | 1.944 |
| 22/12 | 61.39° | 183.3% | 2.088 |
| 24/12 | 63.43° | 200.0% | 2.236 |
Notes and limits
- Angle finders and phone apps read in degrees; plans, shingle instructions and the IRC use pitch in 12. Convert before comparing.
- A 12/12 roof is 45°. Beyond that the pitch number grows fast: 24/12 is 63.4°.
Frequently asked questions
What is a 4/12 pitch in degrees?
18.43°.
What is a 6/12 pitch in degrees?
26.57°.
What pitch is 30 degrees?
About 6.93 in 12, just under 7/12.
What pitch is 45 degrees?
12 in 12.
Sources
Last reviewed: 26 September 2026. The calculation is covered by automated tests with known answers taken from the sources above. Found an error? Please let us know.
More framing, roofs, decks & fences calculators
- Wall Stud Calculator (Studs, Plates & Headers)
- Rafter Length Calculator (Common Rafters)
- Roof Pitch Calculator (Rise and Run to Pitch)
- Roof Truss Calculator (How Many Trusses)
- Stair Calculator: Rise, Run and Stringer Length
- Deck Joist Span Calculator (IRC Table R507.6 Estimate)
- Deck Beam Span Calculator (IRC Table R507.5 Estimate)
- Deck Board Calculator (Boards, Linear Feet and Screws)
- All 50 construction and woodworking calculators