Quick answer: Divide total wall and ceiling area by the sheet size (32 sq ft for a 4ร8, 48 sq ft for a 4ร12) and add 10% for waste to get the number of drywall sheets.
Estimate drywall (sheetrock) sheets, mud, tape, and screws for any room by square footage. Calculate exactly how many 4x8 or 4x12 sheets you need. Accounts for deductions and ceiling toggles.
Drywall is sold by the sheet, not the square foot, so the real question is how many full 4x8 (32 sq ft) or 4x12 (48 sq ft) sheets it takes to cover your walls โ and whether the ceiling is included. Start by measuring the room's total wall perimeter and multiplying by the wall height to get raw wall area, then subtract the square footage of doors and windows. If you're also hanging drywall overhead, add the ceiling area (length ร width) on top of that. Always round up to the nearest full sheet and build in a 10% waste factor for off-cuts, damaged corners, and butt-joint trimming โ running one sheet short mid-job means a same-day store run and a visible seam where the batches don't quite match.
Standard 1/2" drywall works for most living spaces. Bathrooms, laundry rooms, and basements should use moisture-resistant ("green board") or paperless drywall to resist mold. Garage walls shared with living space, and walls around furnaces, typically require 5/8" Type-X fire-rated drywall by code โ check your local building department, since requirements vary by jurisdiction.
Longer 4x12 sheets cost slightly more per sheet but cover 50% more area and cut your seam count dramatically on long walls โ fewer seams means less mud, less tape, and less sanding time. The tradeoff is weight and maneuverability: a 4x12 sheet of 1/2" drywall weighs around 75 lbs and is awkward for one person to hang alone, especially on ceilings.
Only if you are hanging drywall on the ceiling. If you are only drywalling the walls, toggle the ceiling option to "No" to save money on materials. A standard 12x12 room with 8ft walls has 384 sq ft of wall space, plus 144 sq ft of ceiling space.
A 10x10 room with 8-foot ceilings has 320 sq ft of walls. If you include the 100 sq ft ceiling, you have 420 sq ft total. Minus deductions for doors/windows, you will need roughly 13 to 14 standard 4x8 sheets (including a 10% waste factor).
1/2" is standard for most walls and ceilings on 16" on-center framing. Use 5/8" for ceilings on 24" on-center framing (to prevent sagging) and for any fire-rated wall assembly required by code.
A standard 4x8 sheet of 1/2" drywall weighs approximately 57 lbs. A 4x12 sheet of the same thickness weighs roughly 85 lbs โ factor this into how many people you'll need to hang ceiling sheets safely.
Every constant this calculator uses and where it comes from, so you can check it rather than take our word for it.
Local codes amend the model IRC and adopt different cycles — your building department governs. Manufacturers revise yields; where your product's data sheet disagrees with a default here, use the product's number. See our full methodology.