Wall Area for Paint Calculator
Perimeter × ceiling height − doors and windows = paintable area.
Result
Paintable area
355 ft²
400 gross − 45 for doors/windows.
- Gross wall area400 ft²
- Doors (21 ft² each)1 × 21 = 21 ft²
- Windows (12 ft² each)2 × 12 = 24 ft²
- Paintable355 ft²
Step-by-step
- Gross = perimeter × height = 50 × 8 = 400 ft².
- Subtract: 1×21 + 2×12 = 45 ft².
- Paintable = 355 ft².
How to use this calculator
- Measure room perimeter (sum all wall lengths).
- Enter ceiling height.
- Count doors and windows.
About this calculator
Wall area for paint is room perimeter × ceiling height, minus the area of doors and windows you don't plan to paint. Standard openings: door = 21 ft² (3×7); window = 12 ft² average (varies). For exact projects, measure individual openings.
Frequently asked
Don't need to paint glass or door surfaces — those are usually a different finish. Subtracting gives paintable wall area.
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