Home & Construction
Paint Calculator
Estimate wall area and how much paint you need in liters and gallons after subtracting doors and windows.
Paint calculator
Estimated paint
8.7 L
- Wall area
- 48.6 m²
- Paintable area
- 43.74 m²
- Gallons (US)
- 2.31 gal
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How it works
Enter room length, width, and wall height, plus the number of doors, windows, and coats. Openings are subtracted using typical door and window sizes, then coverage of 10 m² per liter is applied.
Formula
Wall area = 2 × (length + width) × height. Paintable area = wall area − (doors × 1.86 m² + windows × 1.5 m²). Liters = paintable area × coats ÷ 10.
Example
A 5 × 4 m room with 2.7 m walls, one door, two windows, and two coats needs about 9 liters of paint.
Frequently asked questions
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