Construction
Roof Pitch Calculator
Pitch ratio and angle from rise and run.
Free to use — no sign-up or login.
Pitch (rise/run)
Angle (°)
Amortization schedule
| # | Date | Payment | Principal | Extra | Interest | Balance |
|---|---|---|---|---|---|---|
Pitch is rise divided by run. Rise 6 and run 12 is 0.50. The angle is arctangent of that ratio, 26.6 degrees.
Stair geometry is the stair stringer calculator. The sketch is the rise-over-run triangle.
Same unit on rise and run
Inches with inches, or feet with feet. Mixing them changes the ratio.
Pitch and angle
Pitch stays a decimal ratio to two places. The angle uses one decimal degree.
Worked example: 6 in 12
Rise 6, run 12. Pitch 0.50. Angle 26.6 degrees.
\[ \theta = \arctan(6/12) \]
Frequently asked questions
What does the roof pitch calculator measure?
6 over 12 is pitch 0.50 and 26.6 degrees.
How many decimal places does roof pitch calculator show?
6 over 12 is pitch 0.50 and 26.6 degrees. Lengths, areas, volumes, and money use two decimals. Purchase counts are whole numbers.
Does roof pitch calculator include waste?
There is no waste term. This is a slope, not a shingle count.
Can roof pitch calculator mix units?
No. roof pitch calculator expects every input in the unit printed on its label.
Is roof pitch calculator a code or structural check?
No. roof pitch calculator is a quantity estimate. Local rules and site conditions stay outside the formula.
References
Assumptions and limitations
The triangle is a straight rise and run. It is not a rafter-length or code check.