How Much Paint for a 12x12 Room?
A 12x12 room has 144 sq ft of floor area and roughly 384–480 sq ft of wall surface, depending on whether the ceiling is 8, 9, or 10 feet high. With 8-foot ceilings, one standard door (20 sq ft), one window (15 sq ft), and two coats of eggshell/satin paint at 375 sq ft per gallon, you need 2 gallons for the walls. That is based on 349 sq ft of paintable wall area: (48 ft perimeter × 8 ft height) minus 35 sq ft for the door and window.
Calculate Your Exact Amount
Enter your ceiling height, doors, and windows to confirm gallons for your specific 12x12 room.
Exact Calculation for 12x12 Room
How We Calculate This
- Measure all four walls: (12+12) × 2 × 8 = 384 sq ft
- Subtract doors and windows: 1 door (20 sq ft) + 1 window (15 sq ft) = 35 sq ft
- Paintable wall area: 384 − 35 = 349 sq ft
- Gallons for 2 coats: (349 × 2) ÷ 375 = 1.86 gallons, rounded to 2 gallons
Pro tip: Always buy an extra quart for touch-ups
What Changes This Amount?
- •Ceiling height: 9 ft ceilings need 2.5 gallons; 10 ft ceilings need 2.5 gallons for two wall coats
- •Paint type: Flat paint covers more (425 sq ft/gal); high-gloss covers less (325 sq ft/gal)
- •Wall texture: Rough walls absorb 20% more paint
- •Color change: Dark to light may need a third coat
Related Resources
FAQ
How much paint is needed for a 12x12 room?
For a 12x12 room with 8-foot ceilings, two coats of eggshell/satin paint, one door, and one window, you need 2 gallons for the walls. The walls total 384 sq ft before openings; subtracting 35 sq ft for a door and window leaves 349 sq ft of paintable surface. At 375 sq ft of coverage per gallon and two coats, that works out to 1.86 gallons, rounded up to 2 gallons.
How much paint for a 12x12 room?
A 12x12 room with standard 8-foot ceilings typically needs 2 gallons for two wall coats. Calculate wall area as (12 + 12) × 2 × 8 = 384 sq ft, subtract 35 sq ft for one door and one window to get 349 sq ft, then divide by 375 sq ft per gallon and multiply by 2 coats. Rooms with 9- or 10-foot ceilings need 2.5–2.5 gallons for walls alone.
How many gallons of paint for a 12x12 room?
Plan on 2 gallons for a standard 12x12 room with 8-foot ceilings and two coats on the walls. Our calculator uses the same formula: 349 sq ft of paintable wall × 2 coats ÷ 375 sq ft per gallon = 1.86 gallons, rounded to 2 gallons. Buy a full 2-gallon set rather than 1.5 gallons so you are not short on the second coat.
Do I need to paint the ceiling too?
A 12x12 ceiling is 144 sq ft. At 400 sq ft per gallon and two coats, the ceiling alone adds about 0.75 gallons (rounded to 1 gallon purchased). Combined with 2 gallons for the walls, a full walls-and-ceiling job in a 12x12 room typically requires about 3 gallons total.
What if my 12x12 room has high ceilings?
Higher ceilings add wall area in proportion to height. A 12x12 room with 9-foot ceilings has 432 sq ft of wall (397 sq ft paintable) and needs 2.5 gallons for two wall coats. At 10-foot ceilings, wall area rises to 480 sq ft (445 sq ft paintable), requiring 2.5 gallons for two coats on the walls.