Plywood Calculator
How much plywood do you need? Enter the area to cover.
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Area to cover—
Estimated cost—
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How this calculator works
A 4×8 ft sheet of plywood covers 32 sq ft. The calculator divides your area by 32 and adds 10% for cuts and waste.
Worked example — a 20 ft × 12 ft subfloor:
240 sq ft × 1.10 = 264 ÷ 32 = 9 sheets.
Subfloor, sheathing or roof?
The sheet math is the same for floors, walls and roofs — just enter the total area you’re covering. Thickness affects price, not sheet count.
Frequently asked questions
How many square feet in a sheet of plywood?
A standard 4×8 ft sheet covers 32 square feet.
How much extra plywood should I buy?
About 10% to cover offcuts and the occasional damaged sheet.
Planning a wall or paint project
Surface condition matters as much as area. Rough, porous, repaired, or strongly colored surfaces may need extra primer or paint. Check the coverage printed on the product you plan to use and account for trim, ceilings, openings, and a second coat where applicable.
How to use this estimate
- Measure the project in the units shown and recheck your measurements before ordering.
- Use the waste allowance as a planning buffer, not as a substitute for a detailed material takeoff.
- Compare the result with the package yield, coverage, or weight listed by your supplier.
- Prices are user-entered estimates and may change by location, product, delivery, and season.
Accuracy and limitations
Calculapedia provides educational planning estimates. It does not inspect your site, select products, guarantee quantities, or replace a contractor, engineer, architect, building official, or supplier. Confirm the final quantity and any safety or code requirements before buying or building.