Paint Calculator
Enter your room size, doors, windows and coats to see how many gallons of wall paint to buy. It is meant for DIY painters doing a bedroom, living room or any interior space.
Common questions
How does the paint calculator work?
It multiplies room perimeter by wall height, takes off 20 sq ft per door and 15 sq ft per window, and assumes about 350 sq ft per gallon per coat. Gallons are rounded up.
Does it include the ceiling or trim?
No, walls only. Calculate ceilings separately, and trim usually needs a quart or two of its own paint.
What if my paint covers more or less?
Coverage on the can can range from about 250 to 400 sq ft per gallon. Rough, porous or dark-to-light jobs often need more paint or an extra coat.
How many coats do I need?
Two coats is the default and the usual advice. One coat can work for a fresh coat of the same color.