Calculators
Roofing Calculator
Estimate roof area and squares.
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About the Roofing Calculator
Enter your building's length and width and the roof pitch (rise per 12) and the calculator estimates the total roof surface area and the number of roofing squares (100 sq ft each) you'll need. It's the starting point for ordering shingles and quoting a roof job.
How to use the Roofing Calculator
- 01Enter your building length, width, and roof pitch.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is a roofing square?
A unit equal to 100 square feet of roof area — the standard way roofing materials are sold and estimated.
How does pitch affect roof area?
A steeper pitch increases the actual surface area above the footprint. This tool applies the pitch multiplier for you.