Drywall Calculator
Enter the total wall and ceiling area you're covering (or estimate it from room size). The calculator returns sheet count for 4×8 or 4×12 panels, plus screws and joint compound. Add an optional waste factor for cuts — it's off by default.
Your measurements
4 × 12 ft sheets cover more with fewer seams to tape, but are heavy and awkward. 4 × 8 ft are easier to handle solo and in tight spaces.
Drywall sheets
13 sheets
What to buy
- Screws
- 416 screws(2 lb boxes)
- Joint compound
- 1.8 gal(1 box)
Coarse drywall screws — about 32 per sheet; sold by the 1 lb box.
“Mud” for taping and smoothing the seams — sold in ~4.5 gal ready-mix boxes.
Typical installed cost
Installed, materials + labor — a ballpark to sanity-check bids, not a quote. See the cost breakdown.
Estimates only. Verify against your supplier's coverage figures before ordering.
Footprint
Sheets to buy
13 4 × 8 ft sheets
Coverage
- Area
- 400 ft²
- Sheet area
- 32 ft²
The formula
Sheets = Total area ÷ sheet area × (1 + waste %)
Example: A 12 ft × 12 ft room with 8 ft walls has ~384 ft² of wall — about 12 × 4×8 sheets, or ~14 with a 10% waste factor added.
How it works
- 1Add up all wall and ceiling area you're covering.
- 2Divide by the sheet area: 32 ft² for 4×8, 48 ft² for 4×12.
- 3Optionally add ~10% for waste and cuts, then round up to whole sheets.
Frequently asked questions
Should I use 4×8 or 4×12 drywall sheets?
4×12 sheets cover more area with fewer seams (less taping) but are heavier and harder to handle. Use 4×8 for tight spaces or solo hanging.
How many sheets of drywall do I need for a 12×12 room?
About 14 sheets of 4×8 for the walls with 8 ft ceilings, plus roughly 5 more if you're drywalling the ceiling — call it 18–19 sheets with waste. Enter the total wall-plus-ceiling area above for an exact count.
How much joint compound and how many screws will I need?
Budget about 4.5 gallons of joint compound (one ready-mix box) and roughly 1,000 screws — about three 1 lb boxes — per 1,000 ft² of drywall. The calculator returns both automatically alongside the sheet count.