Home & Cooking
Drywall Calculator
Estimate drywall sheets, screws, joint compound, and tape for any room. Enter dimensions and openings to get a fast materials list.
Room dimensions
4x8 or 4x12 are standard.
Drywall needed
20 sheets
Covers 561 sqft (walls 381 sqft + ceiling 180 sqft), includes 10% waste.
Screws
640
Joint compound
33.9 lb
Tape
600 ft
Frequently Asked Questions about the Drywall Calculator
What sheet size should I use, 4x8 or 4x12?
4x8 sheets (32 sq ft) are easier to handle solo and fit through most doorways, which is why this calculator defaults to them. 4x12 sheets (48 sq ft) cut horizontal seams on tall walls and speed up taping, but they need two people and clear hallway access. Either way, you can enter custom sheet dimensions.
Why does the calculator add 10% waste?
Cuts around outlets, windows, corners, and end pieces leave offcuts you cannot reuse. The calculator subtracts your door and window openings by area first, then adds 10% on top as a standard buffer for rectangular rooms. Bump it to 15% or more for rooms with many angles, arched openings, or cathedral ceilings.
How many screws per sheet of drywall?
The calculator uses 32 screws per 4x8 sheet, which matches the common practice of spacing screws about 12 inches apart in the field and 8 inches along the edges with 1-1/4 inch coarse-thread screws on 16-inch stud spacing. Ceilings need more screws to resist sag, so count those separately if you are doing ceiling work.
How much joint compound and tape do I need?
The calculator estimates about 1.7 lb of pre-mixed joint compound and 30 linear feet of paper tape per 4x8 sheet, enough for three taping coats. These are planning quantities. Buy compound in 4.5-gallon buckets (about 60 lb each) once you know your sheet count, and paper tape comes in 500-foot rolls.
Do I need different drywall for bathrooms or ceilings?
Yes. Use moisture-resistant (green board) or cement board for wet areas like bathrooms, and 5/8 inch Type X sheets for ceilings to prevent sag over long spans. This calculator estimates quantities for standard 1/2 inch gypsum panels. The sheet count it gives holds regardless of thickness or type, but pricing and weight will differ.