Paint Calculator

About Paint Calculator

A paint calculator estimates how many gallons a job needs from the wall dimensions, the number of coats and the paint's coverage rate. Buying paint is a guessing game otherwise - one gallon short means a second trip and a possible dye-lot mismatch, one too many means a shelf of leftover tins. Enter the wall size, coats and coverage, and the gallons needed appear instantly, rounded up to what you would actually buy. Running out of paint partway up a wall is worse than it sounds: a fresh tin, even the same colour, can differ in shade enough to show as a band in the wrong light, so the safe move is buying enough at once from the same batch. This calculator estimates the gallons from wall area, coats and the coverage rate printed on the tin, then rounds up to whole tins because you cannot buy a third of a gallon. It uses plain wall area, so for a close figure subtract large windows and doors and add a little for heavily textured surfaces, which drink noticeably more than smooth drywall. Primer often has a different coverage rate, so run it as a separate calculation.