# Roof Shingle Calculator URL: https://speedycalculator.com/calculators/construction/roof-shingle/ Last updated: 2026-10-25 > The roof shingle calculator works out the bundles of field shingles, ridge cap, starter strip and roofing nails for a roof, from its area or footprint and pitch, and the cost. ## Inputs - Roof area from - Roof area (ft², m², yd², acre) - Footprint length (incl. overhang) (ft, m, in, yd, cm) - Footprint width (incl. overhang) (ft, m, in, yd, cm) - Pitch (rise per 12) (/12) - Waste (%) - Bundles per square - Ridge length (ft, m, in, yd, cm) - Hip length (ft, m, in, yd, cm) - Eaves + rakes length (ft, m, in, yd, cm) - Ridge cap coverage per bundle (ft, m, in, yd, cm) - Price per bundle (field) (/piece) - Price per bundle (ridge cap / starter) (/piece) ## Results - Roof area - Squares - Field shingle bundles - Ridge cap bundles - Starter strip bundles - Roofing nails - Nails (lb, ≈ 140 per lb) - Shingle cost ## Formula ``` Squares = roof area × (1 + waste) ÷ 100 ft² Field bundles = squares × bundles per square Ridge cap bundles = (ridge + hips) ÷ coverage per bundle Starter bundles = (eaves + rakes) ÷ 105 ft; nails ≈ 320 per square ``` ## Explanation Besides field shingles, every roof needs starter shingles along the eaves and rakes and hip-and-ridge cap shingles over the ridges and hips. Three-tab and most architectural shingles come three bundles to the square; heavy designer shingles may be four or five. ### How to use the Roof Shingle Calculator - **Roof area from** - **Roof area** - **Footprint length (incl. overhang)** - **Footprint width (incl. overhang)** - **Pitch (rise per 12)** - **Waste** - **Bundles per square** - **Ridge length** - **Hip length** - **Eaves + rakes length** - **Ridge cap coverage per bundle** - **Price per bundle (field)** - **Price per bundle (ridge cap / starter)** Results update as you type, and every field accepts the units shown in its menu. ### How it works Choose whether to enter the roof area or the footprint and pitch, then the waste, bundles per square, lengths of ridges, hips, eaves and rakes, and prices. ### Tips for an accurate estimate - Measure the footprint from the ground and apply the pitch multiplier rather than climbing on the roof. - Add 10% waste for simple gable roofs and 15–20% for hips, valleys and dormers. - Confirm design snow and wind loads with your local building department before changing framing or roofing. - Always work with fall protection; roofing is one of the most dangerous trades. ### Common mistakes to avoid - Using the footprint area instead of the sloped roof area when ordering materials. - Forgetting starter strips, ridge caps, drip edge and underlayment. - Mixing up pitch (rise per 12 in of run) with the roof angle in degrees. ### Inputs explained FieldWhat to enterRoof area fromChoose one: Roof area I measured, Footprint and pitchRoof areaUnits: ft², m², yd², acreFootprint length (incl. overhang)Units: ft, m, in, yd, cmFootprint width (incl. overhang)Units: ft, m, in, yd, cmPitch (rise per 12)In /12WasteIn %Bundles per squareChoose one: 3 (3-tab, most architectural), 4, 5 (heavy designer)Ridge lengthUnits: ft, m, in, yd, cmHip lengthUnits: ft, m, in, yd, cmEaves + rakes lengthUnits: ft, m, in, yd, cmRidge cap coverage per bundleUnits: ft, m, in, yd, cmPrice per bundle (field)Units: /piecePrice per bundle (ridge cap / starter)Units: /piece ### What each result means - **Squares** = [Roof area]×(1 + [Waste]÷100)÷9.290304 - **Field shingle bundles** = ceil([Squares]×[Bundles per square] - 0.000001) - **Ridge cap bundles** = ceil(([Ridge length] + [Hip length])÷[Ridge cap coverage per bundle] - 0.000001) - **Starter strip bundles** = ceil([Eaves + rakes length]÷(105×0.3048) - 0.000001) - **Roofing nails** = ceil([Squares]×320) - **Nails (lb, ≈ 140 per lb)** = [Roofing nails]÷140 - **Shingle cost** = [Field shingle bundles]×[Price per bundle (field)] + ([Ridge cap bundles] + [Starter strip bundles])×[Price per bundle (ridge cap ÷ starter)] ### Example values How the main result changes when **Roof area** changes and everything else stays at the example values above: Roof area (ft²)Field shingle bundles1,000471,500472,000472,500473,000474,00047 ## Worked example Inputs — Roof area from: Footprint and pitch; Roof area: 2,000 ft²; Footprint length (incl. overhang): 42 ft; Footprint width (incl. overhang): 30 ft; Pitch (rise per 12): 6 /12; Waste: 10 %; Bundles per square: 3 (3-tab, most architectural); Ridge length: 42 ft; Hip length: 0 ft; Eaves + rakes length: 144 ft; Ridge cap coverage per bundle: 33 ft; Price per bundle (field): $38 /piece; Price per bundle (ridge cap / starter): $55 /piece. Results — Roof area = 1,409 ft²; Squares = 15.5; **Field shingle bundles = 47**; Ridge cap bundles = 2; Starter strip bundles = 2; Roofing nails = 4,959; Nails (lb, ≈ 140 per lb) = 35.4; Shingle cost = $2,006.00. ## FAQ **How many bundles of shingles per square?** Three for 3-tab and most architectural shingles. **How many nails per square of shingles?** About 320 with four nails per shingle, 480 in high-wind areas (six nails). **Do I need starter shingles?** Yes, along all eaves and usually rakes; they seal the first course and prevent blow-offs. **What formula does the Roof Shingle Calculator use?** Squares = roof area × (1 + waste) ÷ 100 ft². ## Sources - [Asphalt Roofing Manufacturers Association](https://www.asphaltroofing.org/)