Paint Calculator
Calculate how many gallons of paint you need based on room dimensions, windows, doors, and number of coats.
Room Dimensions
Gallons Needed
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Quarts Needed
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Wall Area (sq ft)
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Paintable Area
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How this was calculated
Wall area: perimeter (2 x length + 2 x width) x height. Plus ceiling area (length x width) if selected.
Deductions: Standard door = 21 sq ft (3 x 7 ft). Standard window = 15 sq ft (3 x 5 ft).
Coverage: 350 sq ft/gallon is typical for flat/eggshell latex. Textured walls may be 250-300 sq ft/gal.
Gallons: (paintable area x coats) / coverage, rounded up.
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Book a free strategy call →Paint Estimating Tips
One gallon of paint typically covers 350-400 sq ft on smooth surfaces. Textured or porous surfaces may need 250-300 sq ft per gallon. Always apply at least two coats for uniform color, especially when changing from a dark to light color.
Premium paints with higher solids content offer better coverage per coat but cost more per gallon. For large projects, the time savings from fewer coats often offsets the higher paint cost.
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