How Much Paint for a 12x12 Room?
Estimate gallons of paint for a 12 by 12 room using wall height, openings, coats, coverage, and waste.
Last updated: May 2026
Who this guide is for
This guide targets one of the most common room-painting searches: a standard 12x12 room with typical walls, doors, and windows.
What to compare
Wall height, number of coats, coverage per gallon, and whether you subtract windows or doors can change the estimate.
Buying guidance
Use the paint calculator with your wall height and coats, then buy enough for touch-ups if the color change is strong or the surface is rough.
Use the calculator first
Start with the related calculator, then use this guide to interpret the result. Sizes, costs, capacities, and product ratings should always be checked against current labels, reviews, and your actual room or aquarium setup.