How Much Paint for a 12x12 Room?

A 12 × 12 ft room with 8 ft walls, one door and two windows has about 333 sq ft of wall. Two coats take 1.9 gallons, so buy 2 gal of wall paint. Painting the ceiling too adds 1 gal.

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Measure by
Check the can: usually 250–400

Enter your measurements to see the result.

How it's worked out

  1. Wall area: 2 × (12 + 12) × 8 ft = 384 sq ft
  2. Minus openings: 21 sq ft for the door and 15 sq ft for each window = 333 sq ft
  3. Two coats: 333 × 2 = 666 sq ft
  4. Gallons: 666 ÷ 350 sq ft per gallon = 1.9 gal

12x12 room: other ceiling heights

WallsWall areaPaint for 2 coatsBuy
8 ft333 sq ft1.9 gal2 gal
9 ft381 sq ft2.2 gal2 gal + 1 qt
10 ft429 sq ft2.5 gal2 gal + 2 qt

The ceiling is 144 sq ft and takes 0.8 gallons for two coats. Use ceiling paint, which is flatter and spatters less.

Coverage of 350 sq ft per gallon is typical for smooth, previously painted walls. Textured walls, fresh drywall and big color changes use more, so check the label on your can and change the coverage in the calculator.

Other common sizes

More detail: How Much Paint Do I Need for a Room? A Simple Guide