Roof Pitch Calculator
Calculate roof slope, angle, and pitch. Perfect for roofing projects, construction, and architectural planning.
Roof Pitch Calculator
Roof Pitch Results
Enter roof measurements to calculate pitch
Roof Pitch Information
Common Roof Pitches
- • Flat Roof: 0-2:12 (0-9.5°)
- • Low Slope: 2-4:12 (9.5-18.4°)
- • Conventional: 4-6:12 (18.4-26.6°)
- • Steep: 6-9:12 (26.6-36.9°)
- • Very Steep: 9-12:12 (36.9-45°)
Roofing Considerations
- • Material Selection: Varies by pitch requirements
- • Water Shedding: Steeper pitches shed water better
- • Wind Resistance: Lower pitches resist wind better
- • Cost: Steeper pitches cost more to build
- • Maintenance: Steeper pitches are harder to maintain
About the Roof Pitch Calculator
Our free roof pitch calculator finds pitch (rise over run), angle in degrees, and rafter length from span and rise. Enter two values to get the rest. Use it for roofing and construction. Pitch is often given as ratio (e.g. 4:12) or angle. For area of a roof use our area calculator.
You may also find our area calculator useful.
Frequently Asked Questions
What is roof pitch?
Roof pitch is the slope: rise (vertical) over run (horizontal). Often expressed as ratio (e.g. 4:12) or as an angle in degrees.
How do I calculate rafter length?
From span and rise, rafter length = √(span/2)² + rise². This calculator does it when you enter span and rise or pitch.
What pitch is best for my climate?
Steeper pitches shed snow and rain better; flatter pitches suit dry climates. Local building codes often specify minimum pitch.