Paint for common room sizes
| Room (ft) | Wall area* | Two coats needs | Buy (walls) | Ceiling, two coats |
|---|---|---|---|---|
| 8 × 10 | 237 sq ft | 1.4 gal | 1 gal + 2 qt | 2 qt |
| 10 × 10 | 269 sq ft | 1.5 gal | 1 gal + 3 qt | 3 qt |
| 10 × 12 | 301 sq ft | 1.7 gal | 1 gal + 3 qt | 3 qt |
| 12 × 12 | 333 sq ft | 1.9 gal | 2 gal | 1 gal |
| 12 × 14 | 365 sq ft | 2.1 gal | 2 gal + 1 qt | 1 gal |
| 14 × 16 | 429 sq ft | 2.5 gal | 2 gal + 2 qt | 1 gal + 2 qt |
| 16 × 20 | 525 sq ft | 3.0 gal | 3 gal | 2 gal |
| 20 × 20 | 589 sq ft | 3.4 gal | 3 gal + 2 qt | 2 gal + 2 qt |
Use your exact room size. Open the paint calculator →
How many square feet does a gallon of paint cover?
| Surface | Coverage per gallon (one coat) |
|---|---|
| Smooth, previously painted interior walls | 350–400 sq ft |
| New drywall (with primer) | about 300 sq ft |
| Textured walls or ceilings | 250–300 sq ft |
| Exterior siding | 250–400 sq ft depending on surface |
How to measure your room
- Add up the length of all walls (the perimeter): for a 12 × 14 room, 12 + 14 + 12 + 14 = 52 ft.
- Multiply by the ceiling height: 52 × 8 = 416 sq ft.
- Subtract about 21 sq ft per door and 15 sq ft per window.
- Multiply by the number of coats, then divide by 350.
Tips for buying paint
- Two coats are standard. One coat only works with paint-and-primer over a similar color.
- Big color change (dark to light or light to dark)? Prime first or plan a third coat.
- A gallon often costs about the same as 2–3 quarts, so round up to gallons.
- Buy all your paint at once so the batch color matches, or mix (“box”) cans together.
- Trim and doors: a quart usually covers the trim in an average room.
Questions
How many gallons of paint for a 12x12 room?
About 2 gallons for two coats on the walls (8 ft ceilings, 1 door, 2 windows), plus about 1½ quarts per coat for the ceiling.
How much paint for a 10x12 room?
About 1.7 gallons for two coats, so 2 gallons (or 1 gallon + 3 quarts).
How much paint for a 20x20 room?
About 3.4 gallons for two coats on the walls, so buy 3 gallons + 2 quarts, or 4 gallons.
How much paint for a ceiling?
Divide the floor area by 350 for each coat. A 12 × 12 ceiling is 144 sq ft, about 0.8 gallons for two coats.