Paint Calculator

Getting an accurate paint estimate starts with accurate measurements. Use a tape measure to find the width and height of each wall you plan to paint. Our calculator uses an average wall width for simplicity, but for the best results, you can calculate each wall individually and add them up. Don't worry too much about subtracting small areas like windows and doors unless they are very large; most painters buy a little extra paint anyway.

This Paint Calculator from Calculator Site makes it easy to turn your measurements into a reliable paint quantity. Just enter the dimensions, how many coats you'll need, and the paint's coverage rate from the tin.

The coverage of a paint is crucial and is always written on the tin, measured in square metres per litre (m²/L). A typical emulsion paint covers around 12-14 m²/L. The surface texture also matters; a newly plastered, porous wall will absorb more paint than a previously painted one. This is why a 'mist coat' (a thinned-down first coat) is often used on new plaster.

Applying two coats is standard practice. The first coat primes the surface and provides a base, while the second coat delivers the final, solid colour and desired finish. Don't be tempted to skip the second coat, as it can lead to a patchy, unprofessional result. For a significant colour change (e.g., dark to light), you might even need a third coat.