Paint Calculator

Buying too much paint is a waste of money, but running out halfway through a wall is a DIY nightmare. Our paint calculator uses standard industry formulas to ensure you get exactly the right amount.

The Math: First, calculate the total surface area by multiplying the room's perimeter by the ceiling height. Then, subtract the area of doors (standard 21 sq ft) and windows (standard 15 sq ft). A standard gallon of paint covers roughly 350-400 square feet per coat.

Ceilings and Trim: Ceiling paint is typically formulated differently (flatter to hide imperfections and less prone to dripping). Trim is usually painted with a semi-gloss or satin finish for durability. If you select these options, the calculator breaks out the quantities separately so you buy the right finishes.

Always err on the side of rounding up to the nearest gallon. Having extra paint for future touch-ups is essential!