Construction Calculators

Drywall Calculator

Calculate how many standard 4x8 drywall sheets are needed to cover the walls of a room.

Wall area —

Sheets needed —

About the Drywall Calculator

This calculator estimates how many sheets of drywall (gypsum board) you need to finish a room's walls. It computes the total wall area and divides it by the coverage of a standard 4ft × 8ft sheet (32 sq ft).

Formula: Wall Area = 2 × (Length + Width) × Height; Sheets Needed = (Wall Area × (1 + Waste %)) ÷ Sheet Area

Add 10% for cuts around outlets, doors and windows. For ceilings, calculate the ceiling's own square footage separately and add it to your sheet count.