Drywall Square Footage Calculator
Calculate drywall area for walls and ceilings, then convert to the number of 4×8 or 4×12 sheets you'll need to order.
Drywall Calculator
Sheet size selection
Standard residential drywall comes in 4×8 sheets (32 sq ft each) and 4×12 sheets (48 sq ft each). Use 4×12 sheets when possible — they're heavier but produce fewer seams, which means less mudding and a smoother finish.
For tall walls (over 8 ft), 4×12 sheets installed horizontally hide the seam at chair-rail height. For ceilings, 4×12 is the standard for professional installs.
Mud, tape, and screws
You'll need joint compound (mud), tape, and screws beyond the sheets themselves. Plan on roughly 1 gallon of mud per 100 sq ft of finished surface for a level-4 finish, plus drywall tape and 1 lb of screws per 200 sq ft.
For full coverage budget, drywall installation runs $1.50–$3.50 per sq ft installed. Materials alone are usually $0.60–$0.80 per sq ft for the sheets, mud, tape, and screws combined.
Pro tips
Use 4x12 when possible
Larger sheets mean fewer seams. Fewer seams mean less mudding and a cleaner finish.
Add 10% for waste
Cuts at corners and openings produce unusable scrap. Order 10% extra.
Don't forget ceilings
A typical room has more ceiling sq ft than the floor — calculate ceilings separately.
Use 5/8" for ceilings
Standard 1/2" sags over time on ceilings. 5/8" is the better choice for ceiling drywall.