Paint Coverage Calculator
Calculate paint liters and gallons needed for walls and ceilings with door/window deduction
m
m
m
Calculation Result
Paint Required
9.12 Liters
Approx 2.41 US Gallons for 2 coatsNet Wall Area
45.6 m²
Net Wall Area (ft²)
490.83 ft²
Standard Coverage
~10 m²/L
How this calculator works
1
Enter room dimensions (length, width, height).
2
Input count of doors and windows to subtract non-painted area.
3
Choose 1, 2, or 3 coats of paint.
Formula & Mathematics
Paint Volume Formula
Liters = [(Wall Area - Openings Area) × Coats] / Coverage Rate (10 m²/L)
Standard wall paint covers ~350-400 sq ft per gallon (approx 10 sq meters per liter).
Worked Example
4m × 3m room with 2.8m height, 1 door, 2 windows, 2 coats
Gross wall area = 2(4+3) × 2.8 = 39.2 m².
• Subtract 1 door (2 m²) and 2 windows (2.8 m²) = 34.4 m² net
• For 2 coats = 68.8 m² total coverage needed
• At 10 m²/L = 6.9 Liters (approx 1.8 Gallons)
You will need approximately 7 Liters of paint.
Frequently Asked Questions
Yes, unprimed fresh drywall or plaster is highly porous and will absorb more paint. Always apply a primer coat first.
You may also like
Related calculators in Construction
Construction Area Calculator
Calculate surface areas for rectangles, circles, triangles, and land plots
constructionCalculate
Volume & Capacity Calculator
Calculate volumes of cubes, cylinders, cones, and spheres in cubic meters and yards
constructionCalculate
Concrete Slab & Footing Calculator
Estimate concrete volume in cubic yards/meters and 60lb/80lb premix bags required
constructionCalculate