Estimate how many gallons of paint you need for a room based on wall dimensions and coverage rate.
Estimate how many gallons of paint you need for a room based on wall dimensions and coverage rate.
Gallons = (Wall Area – Openings) × Coats / 350
40 ft total walls × 8 ft high, 2 coats, 40 sq ft doors/windows → ~2 gallons.
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What is Paint Calculator?
Estimate how many gallons of paint you need for a room based on wall dimensions and coverage rate.
What formula does this use?
This calculator uses: Gallons = (Wall Area – Openings) × Coats / 350
Is this calculator free?
Yes! All calculators on CalcNest AI are 100% free with no account required.
Is my data safe?
Absolutely. All calculations run locally in your browser. We never store or transmit your input data.