Drywall calculator
Calculate drywall sheets, joint compound, tape, and screws needed for a room.
Drop calc results into projects and quotes, invoice through your own Stripe, get paid. Built by a contractor.
Try TradeMaster Pro →How to Estimate Drywall
Measure the room's perimeter and multiply by the ceiling height to get wall area. Add ceiling area if you're drywalling it. Subtract door and window openings, then divide by the sheet size to get your count.
Always round up and order 10-15% extrato account for cuts, waste, and mistakes. It's cheaper to return unused sheets than to make a second trip.
The most common sheet size is 4x8, which is the easiest to handle for DIY projects and fits through standard doorways. Professional drywall crews prefer larger sheets because fewer joints means less taping and a better finished product. A 4x12 sheet installed horizontally on an 8-foot wall means just one horizontal seam instead of two, cutting your taping time significantly.
For 10-foot ceilings, look into 5-foot wide sheetsfrom commercial drywall suppliers. Sizes like 5x10 or 5x12 eliminate the horizontal butt seam entirely on tall walls. These aren't available at Home Depot or Lowe's — you'll need to order from a dedicated drywall supply house, but the labor savings on taping and finishing are worth it.
Sheet Size Guide
- 4x8 — Standard, easiest to handle, works for 8' ceilings
- 4x9 — For 9' ceilings, reduces horizontal seams
- 4x10 — For 9-10' ceilings
- 4x12 — Fewer joints on long walls, heavier to handle
FAQ
How many sheets of drywall for a 12x12 room?
A 12x12 room with 8-foot ceilings has about 528 square feet of wall and ceiling area. That works out to roughly 17 sheets of 4x8 drywall or 11 sheets of 4x12. Always add 10-15% for waste from cuts and mistakes.
Should I use 4x8 or 4x12 drywall?
4x12 sheets are better for long walls because they create fewer joints — but they weigh about 80 lbs each and require a helper. 4x8 sheets are manageable for solo work and small rooms. For most DIY projects, 4x8 is the practical choice.
How much joint compound and tape do I need?
Plan on about 1 gallon of joint compound per 100 square feet of drywall, 1 roll of tape per 500 square feet, and 1 pound of screws per 200 square feet. Buy pre-mixed compound for easier application.
What size drywall should I use for 10-foot ceilings?
5-foot wide sheets (5x10 or 5x12) from commercial drywall suppliers eliminate horizontal butt seams on tall walls. These aren't stocked at Home Depot or Lowe's — check local drywall supply houses. The next best option is 4x10 sheets installed horizontally.