Free Roofing Calculators That Actually Work
Get instant, accurate answers on roof pitch, square footage, slope angle, roofing squares, and replacement cost. No signup, no email — just numbers.
Most popular calculators
- Roof Pitch CalculatorFree roof pitch calculator. Convert between rise/run, angle in degrees, and rafter length. Get pitch as X/12 plus the slope factor for area calculations.
- Roof Square Footage CalculatorFree roof square footage calculator. Get surface area, roofing squares, and shingle bundles needed based on footprint and pitch. Includes overhang and waste.
- Gambrel Roof CalculatorFree gambrel roof calculator. Get surface area and material estimates for two-pitch barn-style roofs. Handles upper and lower slopes with break height.
- Calculate Roofing — Full Material TakeoffCalculate roofing materials for your project: shingles, underlayment, ice & water shield, drip edge, ridge cap, starter, nails, and OSB decking — with material cost estimate.
- Flat Roof Replacement Cost CalculatorEstimate the full cost to replace a flat roof in 2026: TPO, PVC, EPDM, modified bitumen, or BUR — with tear-off, insulation, parapet flashing, and drains itemized.