How much paint for a 12×12 room?
A 12 × 12 ft room with 8 ft ceilings needs about 2 gallons of paint for two coats on the walls. Add 1 more gallon if you're painting the ceiling. Here's the quick math and a chart for nearby room sizes.
The math
For a 12 × 12 room with 8 ft walls:
- Wall area = 2 × (12 + 12) × 8 = 384 sq ft
- Minus openings ≈ 21 sq ft per door + 15 sq ft per window → about 348 sq ft with one of each
- Two coats = 348 × 2 = 696 sq ft ÷ 350 (coverage per gallon) = 1.99 → 2 gallons
Round up to 2 gallons and keep the leftover for touch-ups.
Paint by room size (walls, 2 coats)
| Room size (8 ft walls) | Gallons (2 coats) |
|---|---|
| 10 × 10 ft | 2 gallons |
| 10 × 12 ft | 2 gallons |
| 12 × 12 ft | 2 gallons |
| 12 × 14 ft | 3 gallons |
| 14 × 16 ft | 3 gallons |
Add 1 gallon for the ceiling, and a gallon of primer if you're covering bare drywall, patches, or a dark color.
Different size or ceiling height?
The paint calculator handles any room — coats, doors, windows, the ceiling, and your paint price — in seconds.
Open the Paint CalculatorFrequently asked questions
How many gallons for a 12×12 room?
About 2 gallons for two coats on the walls (≈348 sq ft of wall area × 2 ÷ 350). Add 1 gallon for the ceiling.
Do I need extra for the ceiling?
Yes — a 144 sq ft ceiling takes about 1 gallon, which covers two light coats. Add it to your wall total.
How much for just one coat?
About 1 gallon for one coat on the walls, but most rooms need two coats for an even finish, so 2 gallons is safer.