Drywall Calculator
Estimate sheet counts for four room walls and an optional ceiling.
Calculate your materials
Your estimate
Enter your measurements and select Calculate estimate to see the results.
Estimates are for planning only; verify product specifications and local requirements.
How this drywall calculator works
Drywall quantity starts with the surface area of a room. This calculator totals all four walls, optionally adds the ceiling, subtracts openings, and estimates full sheets using a waste allowance. It does not plan joints, sheet orientation or fire-rated assemblies.
The calculation
Wall area = 2 × (room length + room width) × wall height. Subtract openings and add ceiling area if selected. Sheets = round up(adjusted area × (1 + waste percentage) ÷ sheet area).
Worked example
A 12 ft × 10 ft room with 8 ft walls has 352 sq ft of wall area. Subtract 40 sq ft of openings and add a 120 sq ft ceiling for 432 sq ft. With 10% extra and 4 × 8 sheets, estimate 15 sheets.
Before buying materials
- Check whether the wall system requires specialty or moisture-resistant board.
- Large sheets reduce seams but may be difficult to carry and install.
- Consult applicable building codes for rated assemblies and fastening requirements.
Frequently asked questions
Does it include drywall screws?
No. Screw and compound quantities depend on framing, sheet layout and finish requirements.
Can I exclude the ceiling?
Yes. Uncheck Include ceiling.
Are door and window openings subtracted?
Yes, using the total opening area you enter.