Roof Pitch Tools is a free suite of calculators that helps homeowners, DIY builders and contractors quickly work out roof pitch, angle, surface area, rafter lengths and basic material quantities.
• Roof pitch (rise/run or degrees), angle and slope percentage
• Area multiplier and actual roof surface area for gable or simple hip roofs
• Roofing squares and approximate shingle bundles (with waste factor)
• Common rafter length and length including overhang
The formulas used are standard construction mathematics:
• Pitch = rise ÷ run
• Angle = arctan(rise ÷ run)
• Area multiplier = √(1 + (rise/run)²)
• Roof area ≈ plan area × multiplier
• Rafter length = √(rise² + run²) or run × multiplier
Results are estimates for planning purposes. Complex roofs (multiple pitches, valleys, dormers) require additional calculation or professional measurement.
All calculations run entirely in your browser. No data is uploaded, stored or shared. See our Privacy Policy for details.
These tools are provided for educational and planning use only. Always verify measurements and material quantities with a qualified professional before ordering materials or beginning construction. Local building codes, structural requirements and safety factors must be considered.