Drywall Calculator
Estimate drywall sheets and screws for a wall area.
Results update as you type.
How it works
A drywall calculator tells you how many sheets of drywall and roughly how many screws you need to cover a wall or ceiling, starting from the total area and the size of the sheets you will use. It works out the area one sheet covers by multiplying its width and height — the standard panel is 4 by 8 feet, or 32 square feet — then divides the total area by that figure and adds a waste allowance before rounding up to whole sheets. The built-in ten percent margin matters because real rooms are full of doors, windows, outlets and corners, and every cut around them leaves an offcut that often cannot be reused, while handling and lifting large panels inevitably cracks a few. Ordering the bare minimum almost guarantees a mid-job shortfall. The screw figure, about 32 fasteners per sheet, reflects the usual pattern of screwing along the edges and through the field into framing spaced 16 inches on center. This is a planning estimate for a rectangular area; on complex layouts, subtract only large openings and let the waste margin absorb the small ones. Homeowners, remodelers and drywall crews use it to price a job and load the truck. The area-divided-by-sheet-area method is standard practice because covering a wall is fundamentally about fitting flat panels across a flat surface.
Sheet area = width × height; sheets = ⌈area ÷ sheet area × 1.10⌉; screws ≈ sheets × 32
Sheet width times height gives the area a single panel covers, defaulting to the common 4-by-8-foot sheet at 32 square feet. Dividing the total wall area by that per-sheet area gives how many panels cover the surface exactly. Multiplying by 1.10 adds a ten percent allowance for cuts around openings, breakage and offcuts, and rounding up ensures you buy whole sheets rather than fractions. The screw estimate multiplies the sheet count by 32, a typical fastener count per sheet when screwing into framing spaced 16 inches apart along the edges and through the field of each panel.
Source:Standard construction estimation (area method)
We review all our tools from time to time to ensure accuracy.
Worked example
How to use this calculator
- 1
Enter your values
Enter area to cover.
- 2
Adjust the options
Adjust sheet width and sheet length if they apply — sensible defaults are already set.
- 3
Read your result
Sheets to buy updates instantly as you type — no button to press.
Frequently asked questions
How many drywall sheets do I need per square foot?
Divide the area you are covering by the area of one sheet. A standard 4-by-8-foot sheet covers 32 square feet, so 1,000 square feet of wall needs about 31 sheets before waste and 35 once a ten percent allowance is added. Larger 4-by-12 sheets cover 48 square feet and mean fewer joints to tape, though they are heavier and harder to maneuver in tight spaces.
How much waste should I allow for drywall?
Around ten percent is a sensible default, and this calculator builds that in automatically. The margin covers cuts around doors, windows, outlets and corners, the offcuts those cuts leave behind, and panels cracked during lifting and handling. Rooms with many openings, angled ceilings or small closets waste more, so lean higher for complex layouts. Buying a spare sheet or two is far cheaper than halting the job for a store run.
How many screws does drywall need?
This tool estimates about 32 screws per sheet, which reflects the common pattern of fastening along panel edges and through the field into studs or joists spaced 16 inches on center. Ceilings and fire-rated assemblies often call for closer screw spacing and therefore more fasteners, so treat 32 as a baseline. Always follow the fastener schedule in your local building code for the specific assembly you are building.
Should I subtract doors and windows?
For a quick estimate you can enter the gross wall area and let the ten percent waste margin absorb small openings, since the offcuts around them are rarely reusable. If a room has very large openings — a wide garage door, a picture window or an open stairwell — subtract those areas from the total so you do not badly over-order. For ordinary doors and windows, leaving them in is the safer, simpler choice.
What size drywall sheet should I use?
The 4-by-8-foot sheet is the most common and the easiest for one or two people to handle. Longer 4-by-12 sheets cover more area with fewer seams, which speeds taping and gives a cleaner finish on long walls and ceilings, but they weigh more and are awkward in tight rooms. Enter whatever sheet size you plan to buy and the calculator adjusts the count to match its coverage.