Free job calculator
Paint Calculator
Work out how many litres of paint you need from your wall area, the number of coats and the coverage.
Coverage needed
0 m²
Paint needed
0 L
2.5L tins (approx.)
0
Coverage varies by paint and surface — bare/porous walls drink more on the first coat.
How much paint do you need?
Take the area to paint in square metres, multiply by the number of coats, then divide by the paint's coverage (around 10 m² per litre for most emulsion):
litres = (area × coats) ÷ coverage, + ~10% waste
So 40 m² with 2 coats at 10 m²/L = 80 ÷ 10 = 8 litres, plus a little for waste. To find wall area, multiply each wall's width by its height and add them up; subtract big windows and doors if you want to be precise.
Paint calculator FAQs
How much paint do I need? +
(Area × coats) ÷ coverage, plus ~10% waste. Coverage is usually about 10 m²/L.
What's the coverage per litre? +
Around 10–12 m² per litre per coat for emulsion; less on bare or porous surfaces.
How many coats? +
Two is standard; add a coat or primer for bare plaster or dark-to-light changes.
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