How Many Square Feet Does a Gallon of Paint Cover?
A gallon of paint covers about 350–400 sq ft per coat, but surface, color and paint type change that. Here's a coverage table and how to use it.
A gallon of interior paint typically covers 350–400 square feet per coat on smooth, previously painted walls. That's the number printed on most cans, and it's the default in our paint calculator.
Real-world coverage is often lower. Here's what changes it and what to expect for common surfaces.
Coverage by surface
| Surface | Typical coverage per gallon |
|---|---|
| Smooth, previously painted drywall | 350–400 sq ft |
| New drywall (after primer) | 300–350 sq ft |
| Textured walls or ceilings | 250–300 sq ft |
| Bare wood or masonry | 200–300 sq ft |
| Primer | 200–300 sq ft |
| Exterior siding | 250–350 sq ft |
In metric, 350 sq ft per gallon is about 8.6 m² per litre. Many paints sold in litres quote 10–12 m² per litre.
What lowers coverage
- Porous surfaces such as new plaster, bare wood and unprimed drywall soak up paint.
- Texture adds surface area you can't see on a tape measure.
- Big color changes, especially light over dark, need extra coats.
- Rollers with a thick nap hold and lay on more paint.
- Spraying loses some paint to overspray.
How many gallons for common jobs?
- Small bathroom: about 1 gallon for two coats.
- 12×12 bedroom (walls only): about 2 gallons for two coats.
- Large living room: 3–4 gallons for two coats.
- Ceiling of a 12×12 room: about half a gallon per coat.
Tip: a gallon is about 3.8 litres, and a quart is a quarter gallon (about 90 sq ft per coat). For touch-ups, a quart is often enough.