Wallboard Calculator

Enter room length, width, and ceiling height to get gross wall area (perimeter × height) plus optional ceiling area. Subtract doors and windows for net boardable surface. Boards = ceil(Net Area × (1 + Waste%) ÷ Board Coverage).

Supports standard wallboard panels: 4×8 (32 sq ft), 4×10 (40 sq ft), and 4×12 (48 sq ft) in 1/2" and 5/8" thickness. A 1/2" 4×8 sheet weighs about 39 lb, while a 5/8" 4×8 Type X sheet weighs about 70 lb — plan two-person lifts accordingly.

Joint compound estimated at 0.053 lb per sq ft for a standard 3-coat finish (about 1 gallon per 100 sq ft, or ~475 sq ft per 4.5-gal bucket), tape at 0.37–0.4 linear ft per sq ft, and screws at ~1 per sq ft (32 per 4×8 sheet at 16" o.c., 48 per 4×12 sheet).

Plan outside corner bead (one stick per corner, cut to ceiling height) and select the finish level from Level 1 through Level 5. Level 5 adds a full skim coat and typically requires 50% more compound than a standard Level 4 finish.

Get detailed cost projections for wallboard sheets, joint compound, tape, screws, and corner bead. Adjust unit prices to match local market rates. 2026 material costs run $0.60–$0.75 per sq ft for board, tape, mud, and screws combined, with installed costs at $1.50–$3.00 per sq ft.

Work in feet, inches, yards, meters, and centimeters. Board sizes can be entered in inches or millimeters. All calculations, material counts, and cost estimates update automatically. Fully functional offline with no internet required.