How much paint for a 12x12 room?
A 12x12 room comes to 1.99 gallons for two coats, one hundredth of a gallon under the round number, which is exactly why two gallons is not the buy.
A 12x12 ft room with 8-foot ceilings needs 1.99 gallons of paint for two coats — buy 2 × 1-gallon cans + 1 × quart. That is 384 sq ft of gross wall, 348 sq ft after deducting one door (21 sq ft) and one window (15 sq ft), covered twice against 350 sq ft per gallon. With the standard 10% waste buffer it comes to 2.19 gallons, about $96 of paint. Having it painted runs about $486 for the walls, or $865 with the ceiling and trim.
Rates and coverage figures updated August 2026. Compiled 2026 from sources last updated 2023–2026.What to actually buy
- 2 × 1-gallon cans + 1 × quart of wall color — $96, leaving 0.06 gal spare.
- On the walls, rounding up to 3 full gallons instead costs $120 and leaves 0.81 gal you will not use.
Link to this room with your numbers
Share it, bookmark it, or paste it back into an AI chat — it opens pre-filled.
What a 12x12 room is, and what that means for the job
Builders draw this one twice per floor plan: the kid's room, the guest room, the one that turns into an office. A 12x12 holds a queen bed on one wall, a dresser on another, and a reach-in closet that eats most of a third. That closet matters. The 348 sq ft of net wall counts one 21 sq ft door and one 15 sq ft window and nothing inside the closet, which people skip on the first pass and regret every time the doors open.
Push the furniture to the middle, cover it, and you have about a three-foot aisle at each wall. Enough to cut in and roll, not enough to swing a tall ladder. Bedroom ceilings usually get done the same weekend, since they pick up the same scuffs the walls do: 144 sq ft at 350 sq ft per gallon, one more can on the cart, and it is ceiling paint rather than your wall color. If your room has a bump-out or a second closet, draw it wall by wall instead.
The numbers behind the answer
| Ceiling height | Gross wall | Net wall | 1 coat | 2 coats | 2 coats + waste |
|---|---|---|---|---|---|
| 8 ft | 384 | 348 | 0.99 | 1.99 | 2.19 |
| 9 ft | 432 | 396 | 1.13 | 2.26 | 2.49 |
| 10 ft | 480 | 444 | 1.27 | 2.54 | 2.79 |
The arithmetic is worth seeing once: 384 sq ft of gross wall comes from 2 × (12 + 12) × 8 ft. Take off 21 sq ft for the door and 15 for the window and you have 348 sq ft to cover. Two coats is 696 sq ft of coverage, and at 350 sq ft per gallon that is 1.99 gallons. Every figure on this page comes from that one calculation.
A 12x12 room needs exactly the same paint as a 10x14 (140 sq ft of floor). All of them measure 48 feet around, so all of them have 348 sq ft of wall to cover and all of them take 1.99 gallons — even though the 12x12 has 144 sq ft of floor and the 10x14 has 140. Wall paint follows the perimeter, not the floor area. Stretching a room in one direction while shrinking it in the other changes how much carpet you buy and not how much paint.
What to buy
Buy two gallons and one quart. Two flat gallons is 2.00 against a padded 2.19, so the last wall goes on thin and you can see it. A third full gallon is $40 for paint you would open once. The quart runs about $16, puts materials at $96, and lands you on 2.25 gallons: six hundredths over what the job asks for, which is a touch-up jar rather than a shelf of leftovers.
Painting the ceiling and trim too
| Surface | Area | Paint, 2 coats | Buy |
|---|---|---|---|
| Walls | 348 sq ft net | 2.19 gal | 2 × 1-gallon cans + 1 × quart |
| Ceiling | 144 sq ft | 0.91 gal | 1 × 1-gallon can |
| Trim and baseboard | 45 linear ft | 0.20 gal | 1 × quart |
What changes the answer
Almost nothing keeps a 12x12 under two gallons once the room stops being standard. At 8 ft you need 1.99 gallons; 9 ft takes it to 2.26 and 10 ft to 2.54. Orange peel texture makes it 2.14 and knockdown 2.53. Lose the window and the wall grows, so you climb to 2.07. The two changes that cut the number are openings: a second window brings it to 1.90 and a second door to 1.87, and even 1.87 clears two gallons once waste goes on top.
| Change | Paint needed | Effect |
|---|---|---|
| Baseline | 1.99 gal | the figure this page answers with |
| 9 ft ceiling | 2.26 gal | crosses two gallons |
| 10 ft ceiling | 2.54 gal | crosses two gallons |
| Orange-peel texture | 2.14 gal | crosses two gallons |
| Knockdown texture | 2.53 gal | crosses two gallons |
| Three coats | 2.98 gal | crosses two gallons |
| A second window | 1.90 gal | −0.09 gal — an opening removes wall you would have had to cover |
| No window at all | 2.07 gal | +0.09 gal |
Doing it yourself against hiring it out
| Route | What you pay | What it takes |
|---|---|---|
| Do it yourself | $96 of paint, plus roughly $19 of sundries | 2 × 1-gallon cans + 1 × quart, one weekend |
| Hire it out | $486 for walls only | about 6.4 painter-hours |
| Hire it out, full room | $865 with ceiling and trim | walls, ceiling and 45 ft of trim |
A single room can also fall under a painter's job minimum, which runs $250–$500 whatever the square footage covers — mobilizing a crew costs the same for one room as for five. If you are pricing work rather than buying paint, the painting estimate calculator builds the full line-itemed bid.
A 12x12 room, answered
How many gallons of paint do I need for a 12x12 room with 8 ft ceilings?
Two gallons plus a quart. The bare requirement is 1.99 gallons for two coats over 348 sq ft of net wall: 48 ft of perimeter at 8 ft, less a 21 sq ft door and a 15 sq ft window. Add the standard 10% for roller waste, tray loss and the section you go back over, and you are at 2.19 gallons. Two gallons will not close the room out. Two gallons and a quart will, with a little left.
Does a 12x12 room really need the same paint as a 10x14 room?
Yes, both need 1.99 gallons. Wall paint follows perimeter, not floor area, and both rooms run 48 ft around: 12+12+12+12 and 10+14+10+14. Both leave 348 sq ft of net wall once one door and one window come out, so both take the same two coats and the same buy. The 12x12 has 144 sq ft of floor and the 10x14 has 140, a difference the walls never see. Shape changes how you move around a room, not what you carry home.
How much does it cost to paint a 12x12 room?
About $96 in materials, or roughly $486 to hire out. The $96 is two gallons and a quart at $40 a gallon; builder-grade paint at $20 halves that and premium at $80 doubles it. The $486 works out near $1.40 per sq ft across 348 sq ft of paintable wall, in the lower half of the usual $1.00 to $3.00 range. See the cost basis, and watch for a $250 to $500 job minimum on a single room.
How much paint for a 12x12 room with 9 ft ceilings?
2.26 gallons, up from 1.99. The extra foot of height runs the full 48 ft perimeter, so it adds 48 sq ft of wall, 396 sq ft instead of 348, and two coats of that is 2.26 gallons, or 2.49 with waste. That is still two gallons and two quarts, not three gallons. Go to a 10 ft ceiling and you are at 2.54 gallons, where the third full can finally becomes the cheaper container.
Sources and method
Coverage rates come from Sherwin-Williams and Benjamin Moore product data sheets; cost ranges were compiled in August 2026 from HomeGuide and Angi/HomeAdvisor, whose own pages date from 2023 to 2026. Angi owns HomeAdvisor, so those are one source and not two. Quantities on this page assume 350 sq ft per gallon per coat on smooth primed drywall, a 21 sq ft door and a 15 sq ft window; sources put windows anywhere from 10 to 16 sq ft, so change the opening counts in the calculator if yours differ. The full constants are on the paint coverage chart, and the cost basis is set out on interior painting cost per square foot.
This is an estimate for planning, not a quote. Measure your own room before buying.