Drywall Calculator
Count 4×8 drywall sheets from wall area minus openings
This counts 4×8 sheets for one wall. The wall area minus openings is divided by 32 square feet. Waste is a separate line, so you can see the exact count before you add a spare. For paint on the same wall, use the paint calculator.
Calculator Inputs
Doors and windows, in square feet, subtracted from the wall.
Shown on its own line. It is not baked into the exact sheet count.
Results
Enter values above to see your results
How to use this calculator
- Enter the wall length and height in feet.
- Enter the square feet of doors and windows to subtract. Use 0 if the wall is blank.
- Set a waste percent. The exact sheet count stays separate from the order quantity.
How the calculation works
Gross area is length × height. Net area is gross area minus openings. A 4×8 sheet covers 32 square feet, so the exact sheet count is net area ÷ 32.
The waste line is that exact count times 1 plus the waste percent. The order quantity rounds that line up to a whole sheet. Screws and joint compound are not estimated here, because the amount depends on the joint style and the brand.
A blank 12 by 8 wall
Twelve feet by eight feet is 96 square feet. Divided by 32, that is exactly 3 sheets. Ten percent waste is 0.3 of a sheet, so the order line is 4 sheets. The exact line stays at 3.
Worked example
12 ft × 8 ft wall, no openings, 10% waste
12 × 8= 96 sq ft96 ÷ 32= 3.00 sheets3 × 1.10= 3.30 sheets, order 4Tips & Best Practices
- •A standard door is about 21 square feet. Measure yours rather than guessing if the opening is unusual.
- •Ceilings and the second face of a wall are extra area. Add them into the length, or run the wall twice.
Frequently Asked Questions
How many sheets of drywall do I need?
Divide the wall area, after openings, by 32. A 12 by 8 foot wall with no openings is 3 sheets of 4×8.
What size sheet does this use?
A 4 by 8 foot sheet, 32 square feet. A 4 by 12 sheet is 48 square feet and is not the divisor here.
Does this count screws or compound?
No. Those depend on the joint and the product. The page only counts sheets, plus a separate waste line.
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