Estimate field-shingle bundles from actual roof surface area or roofing squares, then optionally plan starter products, ridge and hip caps, individual shingles, and material cost.
Start with actual sloped roof surface area. One roofing square equals exactly 100 square feet.
The calculator adds the selected field allowance once, then estimates bundles from manufacturer coverage or an editable bundles-per-square ratio.
base squares = roof area in ft² ÷ 100planning area = base area × (1 + waste % ÷ 100)exact field bundles = planning area ÷ coverage per bundleexact field bundles = planning squares × bundles per squarestarter packages = (eave + optional rake) × (1 + extra rate) ÷ package coveragecap packages = (ridge + hip) × (1 + extra rate) ÷ package coverageA 2,000 ft² roof is 20 squares. With 10% extra it becomes 2,200 ft² or 22 planning squares; at 3 bundles per square, buy 66 field bundles.
A 2,350 ft² roof with 10% extra has 2,585 ft² of planning area. With 33.3 ft² manufacturer coverage, divide 2,585 by 33.3 and round packages upward.
For 180 ft of starter and 100 ft coverage per package, 10% extra gives 198 ft, 1.98 exact packages, and 2 to buy.
A 40 ft ridge plus 80 ft of hips is 120 ft. With 10% extra and 30 ft coverage, 4.4 exact cap packages means buy 5.
Coverage per bundle is preferred when the product specification is available.
Three bundles per square is editable and is not universal across shingle products.
If you only know footprint dimensions and pitch, use Roof Area Calculator before this tool.
Starter and ridge-cap packages may be different products; the combined count is labeled total packages, not shingle bundles.
A roofing square is an area unit equal to 100 ft². Base and waste-adjusted planning squares are displayed separately.
Shingle size, exposure, design, and packaging vary. Manufacturer usable coverage is more reliable than a generic ratio.
Individual shingles are calculated only when shingles per bundle is entered, using whole purchased field bundles. No universal count is assumed.
Starter length combines eaves with optional rake starter. Rake starter is never assumed, and manufacturer linear coverage is required.
Ridge and hip lengths are combined, adjusted separately, and divided by cap-package coverage. The calculator does not assume field shingles can be cut into caps.
Material cost can use field bundle or roofing-square pricing, plus separate starter and cap package prices. It excludes underlayment, flashing, nails, vents, drip edge, sheathing, labor, tear-off, disposal, delivery, and tax.
Divide waste-adjusted roof area by manufacturer coverage, or multiply planning squares by the verified bundles-per-square ratio, then round upward.
It varies. Three is common for some products but is not universal.
Coverage varies by product; use the manufacturer specification.
At 10% extra and a verified 3-bundle-per-square ratio, 22 planning squares requires 66 bundles.
Counts vary. Enter the package count from your product to estimate purchased individual shingles.
Ten percent is a common planning example, not a universal requirement. Complexity and installation details affect allowance.
One roofing square is exactly 100 square feet of roof area.
Add eave length and any intentionally included rake length, apply allowance once, and divide by manufacturer package coverage.
Add ridge and hip lengths, apply allowance, then divide by the cap product's coverage per package.
Do not assume so. Follow the roofing-system manufacturer's instructions.
No. Use Roof Pitch Calculator and Roof Area Calculator first when geometry is not already known.