Drywall Calculator
Calculate 4x8 or 4x12 drywall sheets, screws, and joint compound gallons for interior walls and ceilings.
- 15 × 4×8 ft drywall sheets (1/2" standard)
- 480 × drywall screws (32 per sheet allowance)
- 21.6 gallons joint compound (0.05 gal/sq ft allowance)
Standard Project Worked Example (No JavaScript Required)
Baseline Scenario: 432 sq ft of wall (0% waste): 13.5 → 14 sheets (4×8 ft). With 10% waste: 14.85 → 15 sheets. 576 sq ft room+ceiling: 18 sheets (0%), 20 sheets (10%).
Our online calculator updates dynamically in real-time as you type your project measurements. If JavaScript is disabled, use the formula reference below.
How This is Calculated
Sheets = (Total Area - Openings Deductions) × (1 + Waste% / 100) / Sheet Area (32 sq ft for 4×8, 48 sq ft for 4×12). Fasteners are estimated at 32 screws per 4×8 sheet. Joint compound is estimated at 0.05 gal per sq ft.
Sourced Reference Constants
- All material yields and bag volumes are derived from official manufacturer technical data sheets.
- Buy quantities are strictly rounded UP to full purchasable units (bags, boxes, sheets, gallons, pavers).
- Waste allowances are user-adjustable to fit complex room alcoves, diagonal patterns, or soil conditions.
Frequently Asked Questions
How many square feet does a 4x8 drywall sheet cover?
A standard 4×8 ft drywall sheet covers exactly 32 square feet. A 4×12 ft sheet covers 48 square feet.
How many drywall screws do I need per sheet?
Plan for approximately 32 screws per 4×8 ft sheet when fastening to studs placed on 16-inch centers.
How much joint compound do I need for drywall?
Estimate approximately 0.05 gallons (about 0.7 lbs) of ready-mixed joint compound per square foot of installed drywall.