Drywall calculator
Drywall Calculator
Estimate drywall sheet quantities from wall and ceiling surface area.
Results
- Total surface area
- 400.00 sq ft
- Adjusted area with waste
- 440.00 sq ft
- Sheets required
- 14 sheets
Save this calculation to a project estimate.
What this calculator does
This calculator combines wall area and ceiling area, applies the selected waste allowance, and divides by the selected drywall sheet size.
Use it for planning sheet quantities before checking room layout, seams, openings, delivery limits, and supplier availability.
Sheet sizes
The sheet options use common 4x8, 4x10, and 4x12 panels with areas of 32, 40, and 48 square feet.
Formula used
Total surface area equals wall square footage plus ceiling square footage. Waste is applied to that area, then the result is divided by sheet area and rounded up to a whole sheet count.
Waste allowance
Waste helps account for cuts, layout decisions, damaged panels, and offcuts that cannot be reused. Sheet counts are rounded upward because drywall is purchased as whole sheets.
Frequently asked questions
- Can wall area or ceiling area be zero?
- Yes, either field can be zero, but the combined surface area must be greater than zero to produce a result.
- Which drywall sheet size should I select?
- Choose the sheet size you expect to buy or compare options. Larger sheets can reduce seams but may be harder to transport and handle.
- Does this subtract windows and doors?
- No. Enter the surface area you want included in the estimate. For large openings, adjust your measured wall area before entering it.