Mixing paint colours by volume, not by eye

A target colour from two base paints is a ratio problem, not a guess — the same two paints in a different ratio produce a completely different, unrepeatable shade.

Why it works

Without measuring by volume, matching a mixed colour a second time (for touch-ups or a second room) becomes nearly impossible — tiny ratio differences shift a colour more than most people expect.

Do it exactly

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

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