Use this free drywall calculator to plan a home-improvement or DIY project from the measurements and product information you already have.
HomeCalc shows the formula behind the result and keeps product-dependent assumptions editable where possible, so the calculator can match the material, package or supplier you actually plan to use.
HomeCalc calculates wall surface, subtracts openings, optionally adds the ceiling and divides by the selected sheet area.
FREE DRYWALL ESTIMATOR
Drywall Calculator: Sheets Needed for Walls & Ceiling
Estimate drywall sheet count from room dimensions, openings, sheet size and waste allowance.
Estimated result
Estimate drywall sheets from total board area
Drywall sheet count depends on the surface being covered and the area of the selected sheet. HomeCalc calculates wall area from the room perimeter and height, subtracts openings, optionally adds the ceiling and divides by the sheet size.
drywall area × allowance ÷ sheet area = sheets required
What to check before using the result
- Choose the sheet size you actually plan to handle and install.
- Subtract large doors and windows, but do not overcomplicate tiny openings.
- Ceilings add a full room-footprint area when included.
- Board orientation, seams and offcuts can change real sheet usage even when total area is identical.
Sheet layout matters. A leftover strip may not fit the next wall even though its area looks sufficient, so the geometric minimum and the practical sheet order can differ.