Carpenters and framers measure roof slopes in "pitch" (e.g., 4/12 or 6/12), but solar installers, metal fabricators, and architects often need the true roof angle in degrees. Use this pitch to degrees calculator to instantly convert between the two, or consult our degrees to pitch conversion chart below.
Reviewed by Mason Rivera, Founder & Estimation LeadPick the input style that matches your plans or gauge—see the other representations and the slope factor estimators use on footprint area.
Choose inputs for the active mode, then click Calculate.
Every standard x/12 roof pitch converted to degrees, percent grade, and slope factor — no need to run the calculator above for a common value.
| Roof Pitch (x/12) | Angle (degrees) | Percent Grade | Slope Factor |
|---|---|---|---|
| 1/12 | 4.8° | 8.3% | 1.0034662148993578 |
| 2/12 | 9.5° | 16.7% | 1.0137937550497031 |
| 3/12 | 14.0° | 25.0% | 1.0307764064044151 |
| 4/12 | 18.4° | 33.3% | 1.0540925533894598 |
| 5/12 | 22.6° | 41.7% | 1.0833333333333333 |
| 6/12 | 26.6° | 50.0% | 1.118033988749895 |
| 7/12 | 30.3° | 58.3% | 1.1577036657874837 |
| 8/12 | 33.7° | 66.7% | 1.2018504251546631 |
| 9/12 | 36.9° | 75.0% | 1.25 |
| 10/12 | 39.8° | 83.3% | 1.3017082793177759 |
| 11/12 | 42.5° | 91.7% | 1.3565683830083088 |
| 12/12 | 45.0° | 100.0% | 1.4142135623730951 |
Measure or confirm the required geometric inputs before calculation.
Calculate the plan/base value from your measured inputs.
Use rise/run geometry or form-specific factors to convert to true sloped scope.
Translate outputs into practical units such as squares, pieces, or roll counts.
Verify complex intersections, accessories, and local requirements before procurement.
Verify minimum slope requirements for your specific roofing material (e.g. 1/12 for sealed metal, 3/12 for shingles).
Most ordering mistakes happen when assumptions are mixed across units, pitch, and coverage rules. Using Pitch to Degrees Calculator early helps align scope, quantity, and labor planning before supplier pricing or installer scheduling. This reduces reorders, avoids under-counting, and improves quote consistency.
Start with verified dimensions, run conservative waste assumptions, then compare output against product data sheets and field conditions. For cross-checks, pair this page with Roof pitch calculator and Valley angle calculator.
Treat calculator output as a controlled estimate, then validate accessories, overlaps, and edge details separately. Final checks are stronger when you review assumptions with Roof slope multiplier before submitting purchase orders.
A 4/12 roof pitch is exactly 18.43 degrees. You find this by calculating the arctangent of 4 divided by 12.
A 45-degree angle corresponds exactly to a 12/12 roof pitch, because the vertical rise equals the horizontal run (12 inches up for every 12 inches over).
While pitch is easier for framing carpenters using a framing square, degrees are necessary for engineering load calculations, custom metal trim fabrication, and solar panel sun-tracking models.
A 1/12 roof pitch is 4.76 degrees — one of the lowest slopes still classified as a pitched (not flat) roof, typically requiring a fully adhered or sealed low-slope membrane rather than shingles.
A 2/12 roof pitch is 9.46 degrees, the common minimum slope manufacturers allow for asphalt shingles with upgraded underlayment.
An 8/12 roof pitch is 33.69 degrees — a steep residential slope common on traditional and colonial-style homes.
A 10/12 roof pitch is 39.81 degrees, a steep slope that increases material and labor needs versus a standard 6/12 roof.
Planning. Use outputs for budgeting and early scope, then verify dimensions and specifications before procurement.
Accuracy depends on input quality. Better field measurements and realistic assumptions produce better results.
Yes. Most roofing workflows include waste to cover cuts, breakage, and layout inefficiencies.
Reviewed by Mason Rivera, Founder & Estimation Lead
Every calculator on this site is built using manufacturer specifications, industry-standard waste factors, and real-world estimating practices. Formulas are cross-referenced against supplier data sheets, the NRCA Roofing Manual, and IRC Chapter 9 building code. Calculations are for planning purposes — always verify final quantities with your supplier before ordering.
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Use these together for a complete roofing material takeoff.