Paint coverage assumes one coat on a primed wall

A litre of paint claiming 12-14 m² coverage means one thin, even coat on primed drywall — dark-to-light changes, bare plaster, or textured surfaces routinely need a second coat, doubling real consumption.

Why it works

Manufacturer coverage figures are measured under ideal lab conditions — real walls absorb unevenly and colour changes need full opacity, not just an even film, which is why buying "exactly enough" paint so often falls short.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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How much paint do you need for a room?

A litre of paint claiming 12-14 m² coverage means one thin, even coat on primed drywall — dark-to-light changes, bare plaster, or textured surfaces routinely need a second coat, doubling real consumption. Manufacturer coverage figures are measured under ideal lab conditions — real walls absorb unevenly and colour changes need full opacity, not just an even film, which is why buying "exactly enough" paint so often falls short.

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