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Calculate paint gallons for walls and ceilings. Enter room dimensions, coats, and coverage rate to get primer and paint gallons with waste allowance.
Estimate primer gallons from surface area and substrate type. Calculate stain-blocking, drywall, and masonry primer for proper paint prep coverage rates.
Calculate wallpaper rolls from room dimensions and roll size. Account for pattern repeat, waste, and drops for single and double roll coverage estimates.
Include all visible sides of furniture and projects. Open frame metal: both sides of each member.
Area = Sum of all painted faces (L × W each side)Typical 12 oz can: 8–12 sq ft per coat on smooth surface. Primer cans cover similar or slightly less.
Cans = ceil(Area × Coats ÷ sq ft per Can)Light coats prevent runs. Metallic and dark colors need more coats for even coverage.
Total Cans = Primer Cans + Color Cans × Coats + Clear CoatUpdated: July 2026
40 sq ft × 2 color coats ÷ 10 sq ft/can = 8 cans + 2 primer + 2 clear coat = 12 cans total.
Multiple faces sum to 35 sq ft. Chalk spray or enamel: 4–5 cans color after 1 primer can.
One can may cover 4 sq ft with 3 thin coats. Buy 2 cans same lot for color match backup.
Plan aerosol spray paint quantities for furniture refresh, metal railings, and craft projects. Enter surface area, coats needed, and per-can coverage to get can count for primer, color, and clear coat layers.