Free Paint Calculator - Calculate How Much Paint You Need

Calculate how much paint you need for your room with multiple coat and color options.

Formula & Methodology

Standard premium paint covers approximately 400 square feet per gallon. Porous surfaces may require more.

  • Gallons = (Total Wall Area × Coats) / 400

Worked Example

Using the Paint Calculator: apply the formula above to your input values. For instance, Gallons = (Total Wall Area × Coats) / 400. The tool performs each step instantly and shows the result.

Frequently Asked Questions

How much paint do I need?

It divides your total wall area by a gallon’s coverage (about 350 sq ft) and accounts for the number of coats.

How many coats should I plan for?

Two coats is standard for even color and coverage, especially over darker or uneven surfaces.

Should I subtract doors and windows?

For rough estimates you can ignore small openings, but subtracting large ones avoids buying excess paint.

Browse all free calculators