Plywood and OSB Sheet Calculator

Formula

ceil(Length × Width × (1+Waste allowance/100) / (Sheet width × Sheet height))

Planning estimate. Check product specifications and local requirements before purchasing.

Worked example: Plywood Sheet Calculator

Measurements in this example

Length8 m
Width3 m
Sheet width1.22 m
Sheet height2.44 m
Waste allowance10 %

Calculated quantities

Area24 m²
Sheets9

What to check

This calculation uses: Length, Width, Sheet width, Sheet height, Waste allowance. It returns: Area, Sheets.

Measure each face to the true edge and mark openings. Plan sheet orientation before deciding how much of an offcut can be reused.

Net surface with allowance is divided by the usable face area of one sheet or panel and rounded upward.

Check effective coverage after laps, tongues, starter profiles and corner details. Overall panel size may not equal installed coverage.

A total sheet count does not place joints. Framing layout, edge support, expansion gaps and fastening schedule remain essential.

Use the units beside each field. The values in the worked example are starting inputs; replace them with your measurements and the specifications of your material.

Compare alternatives

Open a tool, enter your measured dimensions, then save an estimate. Keep another version if you want to compare products or allowances.

Project sheet

Saved in this browser. Each entry keeps its own measurements. Quantities from different jobs are not added together.

Your sheet is empty. Save a calculation to keep it here.

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