How Much Paint for a 12x12 Room?
A 12x12 room typically needs 2 gallons for two coats on the walls with 8-foot ceilings (about 1 gallon for one coat). That assumes eggshell/satin at 375 sq ft per gallon, one door, and one window — 349 sq ft of paintable wall from 384 sq ft gross.
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
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We'll send your 2-gallon estimate for a 12x12 plus a shopping list of things to get with your paint — brushes, rollers, tape, drop cloths, and touch-up tips.
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Before you calculate
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. At 375 sq ft per gallon and two coats, that is 1.86 gallons, rounded to 2 gallons.
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. Formula: 349 sq ft × 2 coats ÷ 375 = 1.86 gallons, rounded to 2.
How many coats of paint do I need?
Most rooms need two coats for even color and durability. One coat can work when you are refreshing the same or a very similar color on walls in good condition. Dark-to-light changes, stained walls, or new drywall often need a primer plus two finish coats. For a 12x12 room, two wall coats is what our 2-gallon estimate assumes.
Do I subtract doors and windows?
Yes. Subtract about 20 sq ft per standard door and 15 sq ft per average window so you do not overbuy. Our 12x12 estimate subtracts one door and one window (35 sq ft total), leaving 349 sq ft of paintable wall. Add openings back into the calculator if your room has more doors or windows.
What if my ceilings are higher than 8 ft?
Wall area scales with height. A 12x12 room needs 2 gallons at 8 ft, 2.5 gallons at 9 ft, and 2.5 gallons at 10 ft for two wall coats (same door/window assumption). Use the quick calculator if your height is in between.
Do I need extra paint for the ceiling and trim?
Yes if you are painting them. A 12x12 ceiling is 144 sq ft — often about 0.5–1 gallon for two coats of flat ceiling paint. Trim, doors, and baseboards are usually bought in quarts or a separate gallon of semi-gloss. Wall gallons above (2 at 8 ft) do not include ceiling or trim.
Do I need primer, and does it change how much paint I buy?
Primer is separate from finish paint. Use primer on new drywall, stains, glossy surfaces, or big color changes. Plan roughly one primer coat over the same wall area (often close to half your finish gallons, since primer is one coat). Finish paint for a 12x12 room stays at about 2 gallons for two coats once priming is done.
Should I buy gallons or quarts, and how much extra?
Buy gallons for the walls — a 12x12 room typically needs 2 gallons for two coats. Add an extra quart (or keep leftover from an opened gallon) for touch-ups. Quarts alone are only practical for tiny accent areas or trim, not a full 12x12 room.