Paint calculator
Enter the room's size and how many doors and windows it has. Most paints cover 350 to 400 square feet per gallon per coat.
Your estimateEstimate
- Wall area
- 384 ft²
- Doors and windows
- −50 ft²
- Area to paint × 2 coats
- 668 ft²
Paint needed1.91 gal
- Buy
- 2 gallons
How it is calculated
Wall area = 2 × (length + width) × height. Doors and windows are subtracted, and the ceiling (length × width) is added if you tick it.
Paint needed = area × coats ÷ coverage per gallon (or liter).
Worked example
With the starting values shown in the form, the result is 1.91 gal (paint needed). Change any number and the estimate updates as you type.
Tips
- Buy whole gallons for the main color and keep a little for touch-ups.
- A primer coat helps when you cover a dark color or bare drywall.
Questions
- How much paint for a 12 × 12 room?
- With 8 ft walls, one door and two windows, about 334 ft² of wall. Two coats at 350 ft² per gallon need about 1.9 gallons, so buy 2.
- Do I really need two coats?
- Usually yes for an even color, especially when changing colors. Some one-coat paints cover well over a similar shade.
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