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How much paint do you need for a wall?

Liters of paint needed from square meters, coats and coverage — with total cost.

Quick answer

Litres needed = (area m² × number of coats) ÷ coverage per litre. A 40 m² wall with 2 coats and 10 m²/L coverage: (40 × 2) ÷ 10 = 8 litres. Most wall paints cover 8–12 m² per litre per coat.

Paint needed

8 liters

Suggested cans
4 × 2.5 L or 2 × 5 L

Typical wall paint coverage is 8–12 m² per liter per coat. On new or very absorbent surfaces plan an extra coat.

How it works

Buy slightly more than calculated — touch-ups and roller absorption add 5–10%. On new plaster or very absorbent surfaces, plan an extra coat or use primer first; coverage drops on rough or dark surfaces.

Frequently asked questions

How many coats of paint on a new wall?+

Typically primer + 2 finish coats on new plaster. A single coat over an existing similar colour may suffice for refresh jobs.

Does ceiling paint differ from wall paint?+

Ceiling paint is thicker and splatters less overhead. Coverage is similar but application is slower. Count ceiling m² in total area.

Matte vs washable paint — same coverage?+

Coverage is similar per litre, but washable (satin) paints often need an extra coat on dark-to-light colour changes. Check the tin label for exact m²/L.

How do I subtract doors and windows?+

Measure wall area as length × height per wall, subtract openings, or use room perimeter × height minus 15–20% as a quick estimate for standard rooms.

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