Measure first
Measure finished dimensions, actual stock, openings, and site constraints before ordering material.
Roof materials
Roof Shingle Calculator
Estimate a simple gable roof's surface area, roofing squares, and shingle bundles from building length, span, pitch, waste, and bundles per square.
How the estimate works
Use the number as a planning starting point.
The tool turns pitch into a slope multiplier, calculates both roof planes, applies the waste allowance, then converts the result to 100-square-foot roofing squares and bundles.
Check the result
Complex hips, valleys, dormers, flashing, starter strips, ridge caps, ventilation, underlayment, and manufacturer requirements need a detailed takeoff beyond this simple gable estimate.
Plan the next step
Use the related calculators below to turn a first estimate into a material list, layout, or a more detailed project plan.
FAQ
Common Roof Shingle Calculator questions
What is a roofing square?
A roofing square is 100 square feet of roof surface, not 100 square feet of building footprint.
How much shingle waste should I use?
Simple roofs may use a modest allowance; complex roofs with valleys, hips, or many penetrations usually need more.
Related tools
Keep the project moving.
Roof Pitch Calculator
Free roof pitch calculator. Convert rise and run into roof pitch, angle, slope percentage, pitch multiplier, and an approximate common-rafter length.
Open Roof Pitch CalculatorRafter Length Calculator
Free rafter length calculator. Estimate a common-rafter diagonal length from roof rise, run, and overhang for early roof planning.
Open Rafter Length CalculatorRoof Pitch Calculator
Free roof pitch calculator. Convert rise and run into roof pitch, angle, slope percentage, pitch multiplier, and an approximate common-rafter length.
Open Roof Pitch CalculatorPlanning disclaimer: WoodCutTool results are estimates. Verify measurements, product instructions, material condition, local requirements, and safety practices before buying, cutting, or building.