Drywall Calculator
Work out the drywall sheets a project needs from the wall and ceiling area and sheet size, plus screws, joint compound, and tape. Calculates in your browser.
Sheets to buy
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Show the math
Divide the area by one sheet, after adding waste, and round up:
sheets = ⌈area × (1 + waste%) ÷ (width × length)⌉
≈ 0.053 lb compound and 0.37 ft tape per sq ft
A 4×8 sheet covers 32 sq ft; 4×12 sheets cut down on seams for long walls. Screws, compound and tape are rough rules of thumb (32 screws a sheet, about 0.053 lb of compound and 0.37 ft of tape per sq ft), not manufacturer figures; check the coverage on your compound and the fastener spacing your code or installer uses. All math runs locally in your browser.
What this does
A drywall calculator works out the sheets a project needs from the wall and ceiling area and sheet size, plus screws, joint compound, and tape.
How to use it
- Enter the wall and ceiling area.
- Choose the sheet size.
- Add a waste allowance.
- Read sheets, screws, mud, and tape.
How it works
A 4×8 sheet is 32 sq ft. Screws, compound and tape use rough rules of thumb (32 screws a sheet, about 0.053 lb of compound and 0.37 ft of tape per sq ft), not manufacturer figures, so treat them as a shopping guide.
sheets = total area ÷ sheet area × (1 + waste)
Understanding your result
The sheet count plus the compound, tape, and screw estimates give you a full shopping list, with waste built in for cuts. Using longer sheets where they fit reduces the number of joints you have to tape and finish, which is the slow part of the job, so plan the layout for fewer seams and buy a spare sheet against breakage.
Example
A 500 sq ft job in 4×8 sheets needs 18 sheets with 10% waste.
Last updated .
Frequently asked questions
How many sheets of drywall do I need?
Divide the total area by the sheet area (a 4×8 sheet is 32 sq ft) and round up, adding about 10% for waste and offcuts.
How much joint compound and tape?
The tool uses a rough rule of thumb of about 0.053 lb of compound and 0.37 ft of tape per square foot of drywall. It is not a manufacturer figure, so check the coverage on your compound and buy a little extra.
Which sheet size should I use?
4×8 sheets are easiest to handle; 4×12 sheets reduce seams on long walls but are heavier. Enter whichever you’ll buy.
Do you store my numbers?
No. Everything is calculated locally in your browser.
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