Drywall Calculator
Calculate drywall sheets, screws, joint compound, and tape for your project. Enter room dimensions and openings for accurate material estimates.
feet
feet
feet
count
~21 sq ft eachcount
~15 sq ft each%
Material List
—sheets of drywall
Wall Area—
Ceiling Area—
Openings Deducted—
Net Area + Waste—
Screws (~30/sheet)—
Joint Tape—
Joint Compound—
Formula Used
Sheets = (Wall Area + Ceiling − Openings) × Waste ÷ Sheet Size
How to Calculate Drywall
Calculating drywall requires measuring wall and ceiling areas, subtracting openings, and adding waste. Drywall is sold in sheets — the two standard sizes are 4×8 feet (32 sq ft) and 4×12 feet (48 sq ft).
Drywall Formula
Sheets = [(Perimeter × Height) + Ceiling − Openings] × (1 + Waste%) ÷ Sheet Size
Drywall Accessories Per Sheet
| Material | Per 4×8 Sheet | Per 100 sq ft |
|---|---|---|
| Drywall Screws | 28-32 | ~90 |
| Joint Tape | 12 ft | ~37 ft |
| Joint Compound | 3.5 lbs | ~11 lbs |
| Corner Bead (if needed) | Varies | Linear foot basis |
Drywall Cost Estimator
| Drywall Type | Cost per Sheet (4×8) | Use Case |
|---|---|---|
| Regular 1/2" | $10-$15 | Standard walls |
| Fire-Rated 5/8" (Type X) | $14-$20 | Garages, ceilings, fire walls |
| Moisture-Resistant (Green) | $15-$22 | Bathrooms, kitchens |
| Mold-Resistant (Purple) | $18-$28 | High-moisture areas |
| Soundproof (QuietRock) | $45-$60 | Media rooms, bedrooms |
Common Drywall Mistakes
- Not enough waste. Plan for 10% waste on simple rooms, 15% on rooms with many angles and cuts.
- Wrong thickness. Building codes require 5/8" Type X on garage walls/ceilings and between floors.
- Forgetting ceiling. Ceiling drywall is often overlooked. It uses the same material but may need more screws (every 12" vs 16").
- Skipping accessories. Budget for screws, tape, mud, corner bead, and sanding supplies.
Drywall Calculator FAQ
Divide total area by 32 (for 4×8 sheets) or 48 (for 4×12). Add 10% waste. A 12×12 room with 8' ceilings needs about 14 sheets.
28-32 screws per 4×8 sheet on walls. 36-40 for ceilings. About 1 lb of screws per 10 sheets.
About 3.5 lbs per 4×8 sheet for 3 coats. A 4.5-gallon bucket covers ~85 sheets.
1/2" for standard walls/ceilings. 5/8" Type X for fire-rated, garages, between floors. Green board for bathrooms.