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Redmoon Converters
🔨 Construction & DIY

Paint Coverage Calculator (Litres / Gallons)

Calculate exact paint needed: wall area minus doors and windows, multiplied by coats and primer, with surface texture coverage factor and brand-specific m²/L.

NameLWHeightDoorsWindows
Paint needed
0 gal
Wall area · Primer
RoomWall areaNet area
How the math works

Wall area per room: 2 × (L + W) × height. Optionally add ceiling = L × W.

Subtract openings: 21 sqft per door, 15 sqft per window (≈ 1.95 m² and 1.4 m²).

Paint needed: total_net_area × coats / coverage_per_gal. Coverage depends on surface texture: smooth 350, light 300, heavy 250 sqft/gal.

Primer: one coat at ~200 sqft/gal across all surfaces. Always round up to whole containers.

Also known as

paint calculatorhow much paint do i needpaint coverage calculator

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