Roofing Shingle Calculator

Building Length

Building Width

Roof Pitch

Waste %

Bundles per Square

✓ Your estimate

Estimated shingles needed

shingle bundles

Switch display unit only.

Roof sq ft

Sq ft incl. waste

Roofing squares

Shingle bundles

View units

Calculate first to see unit conversions.

What this estimate includes

This estimate shows roof square footage, roofing squares, and shingle bundles based on roof pitch, waste, and bundles per square.

How it’s calculated

Roof area = building footprint × pitch factor

Adjusted area = roof area × waste %

Roofing squares = adjusted sq ft ÷ 100

Bundles = roofing squares × bundles per square, rounded up

Before you order

Complex roofs with hips, valleys, dormers, skylights, and multiple slopes need more waste than a simple roof. Confirm measurements with a roofing professional before ordering.

Frequently Asked Questions

What is a roofing square?

One roofing square equals 100 square feet of roof area.

How many bundles are in a square?

Many asphalt shingles use 3 bundles per square, but some products use more. Check the product label.

Does roof pitch matter?

Yes. Steeper roofs have more surface area than the flat building footprint, so the calculator applies a pitch factor.

Disclaimer: This calculator provides estimates only. Actual quantities depend on product coverage, jobsite conditions, waste, and supplier details. Verify all quantities before ordering. See all outdoor material calculators.