Drywall Calculator
Estimate wall and ceiling sheets with common sizes and a waste allowance.
Preparing your calculator…
How this calculator works
Wall area = perimeter × height − opening area. Add length × width for the ceiling if selected. Sheets = ceiling(total area × waste factor ÷ sheet area). Layout, cuts, thickness, screws, tape, joint compound, and labor are not included. Subtract 21 sq ft per door and 15 per window, in addition to other opening area. Accessory allowances are one gallon of compound per 100 sq ft, 0.4 linear feet of tape per sq ft, and 48 screws per purchased sheet; they are planning estimates, not a fastening or finishing specification.
Use current quotes, local rates, and measured dimensions to make this estimate useful for your situation.
Frequently asked questions
How do I use the drywall calculator?+
Enter your measurements or financial assumptions above. Results update instantly. A 12 × 14 ft room with 8 ft walls and a ceiling totals 584 sq ft. At 10% waste and 32 sq ft per sheet, round 20.075 up to 21 sheets.
How accurate is this estimate?+
The arithmetic follows the method described here. Site conditions, product specifications, and installation requirements can affect the actual project. Measure carefully and check manufacturer instructions.