How many square feet does a sheet of plywood cover?

A standard 4×8 sheet of plywood covers 32 square feet. A 4×9 sheet covers 36 sq ft and a 4×10 sheet covers 40 sq ft.

How much waste should I add for plywood?

Add 10% waste for simple rectangular rooms. Add 15% for rooms with many cuts and 20% for diagonal layouts. The calculator lets you set your own waste percentage.

What thickness plywood should I use for subfloor?

Most building codes require 3/4" (23/32") tongue-and-groove plywood for subfloors with joists 16" on center. Use 7/8" for 19.2" OC and 1-1/8" for 24" OC spacing.

What is the difference between plywood and OSB?

Plywood is made from thin wood veneers and is stronger and more moisture-resistant. OSB (oriented strand board) is made from wood strands and is cheaper — commonly used for sheathing and subfloors.

Plywood Calculator

Calculate how many plywood sheets you need for any project. Enter area dimensions and get total square feet, sheet count with waste, and cost estimate.

Area Length (ft)

Area Width (ft)

Sheet Size

Waste %

Sheets Needed

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Total Area —

Waste Sheets —

Extended More scenarios, charts & detailed breakdown ▾

Length (ft)

Width (ft)

Sheet Size

Waste %

Price per Sheet

Sheets Needed

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Area —

Material Cost —

Professional Full parameters & maximum detail ▾

Area Length (ft)

Area Width (ft)

Thickness

Grade / Application

Cut Pattern

Base Waste %

Price per Sheet ($)

Materials

Net Area —

Sheets Needed —

Material Cost —

Installation

Total Weight —

Est. Fasteners (screws/nails) —

Construction Adhesive —

How to Use This Calculator

Enter the length and width of the area in feet.
Select the plywood sheet size (default 4×8).
Results show total square feet, sheets needed, and waste sheets.

Formula

Area (ft²) = length × width

Sheets needed = ceil(area × (1 + waste%) ÷ sheet size)

Example

Example: 20 ft × 30 ft floor with 10% waste → 600 ft² → 20.6 → 21 sheets of 4×8 plywood.

Frequently Asked Questions

A standard 4×8 sheet of plywood covers 32 square feet. A 4×9 sheet covers 36 sq ft and a 4×10 sheet covers 40 sq ft.
Add 10% waste for simple rectangular rooms. Add 15% for rooms with many cuts and 20% for diagonal layouts. The calculator lets you set your own waste percentage.
Most building codes require 3/4" (23/32") tongue-and-groove plywood for subfloors with joists 16" on center. Use 7/8" for 19.2" OC and 1-1/8" for 24" OC spacing.
Plywood is made from thin wood veneers and is stronger and more moisture-resistant. OSB (oriented strand board) is made from wood strands and is cheaper — commonly used for sheathing and subfloors.