Paint Calculator
Calculate how much paint you need for walls and ceilings.
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L Room walls: L
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WFrequently Asked Questions
How much paint do I need for a room?
Calculate total wall area: (perimeter × height) minus doors (typically 2m² each) and windows (typically 1.5m² each). Divide by the paint's coverage rate (typically 10–12 m²/litre for emulsion). Multiply by number of coats. Add 10% as a buffer. A typical bedroom (4m × 4m × 2.4m high) with 2 doors and 1 window needs roughly 5–6 litres for 2 coats.
How many square metres does a litre of paint cover?
Coverage varies by product: thin matt emulsions cover 10–12 m²/litre per coat. Premium paints: 12–14 m²/litre. Gloss and satin finishes: 8–10 m²/litre. Masonry paint: 5–8 m²/litre. Always check the manufacturer's stated coverage on the tin — rough or porous surfaces need more.
How many coats of paint do I need?
Fresh plaster or a dramatic colour change (e.g. dark over light): 3 coats. Standard re-painting with similar colour: 2 coats. High-quality paints may cover in 2 coats where budget paints need 3. White or light over dark almost always needs 3 coats minimum.