Drywall Calculator

How much drywall do I need?

To figure out how much drywall you need, find your wall and ceiling area, add ~10% for waste, then divide by the sheet size — 32 sq ft for a 4×8 sheet or 48 sq ft for a 4×12. You’ll also need about 0.12 lb of joint compound and 0.40 linear feet of tape per square foot, plus roughly one screw per square foot. For example, a 12 ft × 14 ft room with 8 ft walls and a ceiling needs 21 sheets, about 77 lb of compound, 257 ft of tape and 672 screws. Enter your room above for a full materials list you can print or share.

How we calculate drywall

• From a room: wall area = 2 × (length + width) × height (+ ceiling = length × width)
• With waste = area × (1 + waste%) · openings subtracted only if enabled
• Sheets = ⌈ area ÷ sheet size ⌉ (4×8 = 32 sq ft, 4×12 = 48 sq ft)
• Joint compound (lb) = area × 0.12 · one 4.5-gal box ≈ 475 sq ft
• Joint tape (lf) = area × 0.40 (≈ 40 lf per 100 sq ft)
• Screws = sheets × screws per sheet (≈ 1 per sq ft)

How to use this calculator

1. Choose an input mode. Enter room dimensions or a total wall/ceiling area.
2. Add the ceiling. Include the ceiling if you’re boarding it, and pick your sheet size.
3. Set waste. Keep 10% waste, or bump to 15% for cut-heavy rooms with many openings.
4. Read your estimate. See sheets, joint compound, tape and screws, then print or share the list.

Tips & real-world notes

• Don’t subtract small openings by default — the off-cuts around them are usually the waste.
• Use 4×12 sheets on long walls to cut down on hard-to-finish butt joints where framing allows.
• Ceilings use more screws and often 5/8" board for fire and sag rating — heavier to handle.
• Corner bead, outside corners and control joints are separate line items, not in these totals.