Free tool · Finishes
Drywall Calculator
Enter the wall length and height, add any ceiling area, subtract the openings, and choose the sheet size. You get the number of sheets to order, rounded up, with a waste allowance.
The numbers stay in your browser: nothing is saved or sent anywhere.
Sheets to order
—
Enter the wall length above
Area covered
— sq ft
The formula
Net area = (total wall length × height) + ceiling area − openings.
Sheets = net area × sides covered × (1 + waste) ÷ area of one sheet, rounded up to a whole sheet.
A 4 × 8 sheet covers 32 square feet, a 4 × 10 covers 40, and a 4 × 12 covers 48.
A worked example
A room has 40 ft of wall, 8 ft high, which is 320 sq ft. Add 200 sq ft of ceiling and subtract 40 sq ft of door and window openings: 480 sq ft net.
With a 10 percent waste allowance that is 528 sq ft. Divided by 32 sq ft per 4 × 8 sheet, it is 16.5, so order 17 sheets.
Choosing a sheet size and the waste allowance
Longer sheets mean fewer joints on long walls and ceilings, but they are harder to carry and hang. Run the same room at different sizes and compare.
Waste depends on how cut-up the rooms are. Small rooms with many openings waste more than big open spaces, so the allowance box is yours to change.
What this does not include
The calculator counts sheets only. It does not include joint compound, tape, screws, corner bead, framing or labor, and it does not account for fire-rated or moisture-resistant board, which are priced and ordered by type.
FAQ
How many square feet is a sheet of drywall?
A 4 × 8 sheet is 32 square feet, a 4 × 10 is 40, and a 4 × 12 is 48.
Should I subtract doors and windows?
Usually yes for large openings. Some contractors do not subtract small ones because the scrap is rarely usable. Enter the openings you want to take out.
What does “sides covered” mean?
Choose 2 sides if the same wall is covered on both faces, for example an interior partition. Wall length counts each wall once, so the calculator doubles the area for you.
Is anything I type saved?
No. The calculation runs in your browser and nothing is stored or sent to us.
Pricing a whole interior? PoPs Estimating measures drywall from your plans and keeps the quantities tied to the bid.
Questions?
Ask us anything about PoPs Suite, pricing, or running a construction company. A real person answers, usually within a business day.