Paint Quantity Calculator

This calculator works out how many litres of paint you need for a job in New Zealand, from the wall area you are covering, the coverage your paint achieves per litre, and the number of coats. Buying paint is one of those tasks where it is easy to get the quantity wrong, ending up with half a wall left to do or a stack of unopened tins, and because paint is not cheap and colours are mixed to order, getting it right first time matters. The calculation is straightforward: the total area to paint is the wall area times the number of coats, and dividing that by the coverage per litre gives the litres required. You enter the wall area, the coverage per litre stated on the tin, and how many coats you plan, and the calculator returns the litres needed. Most interior wall paints cover around ten to twelve square metres per litre per coat, but porous, rough or previously unpainted surfaces drink more, and painting a light colour over a dark one usually needs an extra coat. Two coats is standard for a good finish, with a primer or sealer first on bare patches. For a quick estimate you can use the full wall area, which builds in a buffer, or subtract big windows and doors for a tighter number. An estimate to plan your project.

Coverage varies; porous or dark-over-light surfaces need more. Two coats is standard, plus a primer on bare patches. An estimate for planning only.