Drywall Calculator

How to Calculate Drywall Sheets

This calculator determines how many drywall sheets you need based on total surface area and sheet size.

The formula

Sheets = Total Area ÷ Sheet Area (rounded up)

Sheet area = Sheet Height × Sheet Width.

Step-by-step

1. Calculate the total surface area to cover (walls and/or ceiling) in square feet.
2. Enter your sheet dimensions (default: 4 ft × 8 ft = 32 sq ft per sheet).
3. The calculator divides and rounds up to the next whole sheet.

Worked example

500 sq ft of wall, standard 4×8 sheets (32 sq ft each). Sheets = 500 ÷ 32 = 15.625, rounded up to 16 sheets.

Standard sheet sizes

• 4' × 8': 32 sq ft (most common for residential walls)
• 4' × 10': 40 sq ft (taller ceilings)
• 4' × 12': 48 sq ft (large rooms, fewer seams)

Add 10–15% extra for waste, cuts around outlets, and mistakes. For a 500 sq ft project, order 18 sheets to be safe.