Accurate paint and material quantities for every decorating project. From interior emulsion and exterior masonry paint to wallpaper and specialist coatings - calculate exactly what you need and avoid unnecessary trips back to the merchant.
Running out of paint halfway through a room is one of the most avoidable problems in decorating. Different batches of the same colour can have slight tonal variations, so buying enough in one go is always the professional approach.
Our decorating calculators account for the specific spread rate of the product type, the number of coats required, the surface texture and porosity, and deductions for doors and windows. They give you an accurate quantity to order rather than a rough guess.
Whether you are a professional decorator quoting a contract job, a builder finishing a new build, or a homeowner redecorating a house, these tools help you buy the right amount first time.
Select a calculator below to get instant material quantities for your decorating project.
Calculate how many litres of paint you need for interior walls and ceilings. Enter room dimensions, ceiling height, number of coats, and deduct doors and windows. Returns total paintable area in m2, litres required per coat, and total litres including your chosen waste allowance. Suitable for emulsion, eggshell, and satinwood finishes.
Use CalculatorEstimate exterior masonry paint or timber paint quantities for outside walls, rendered surfaces, timber cladding, and garden structures. Enter wall area, surface type, and number of coats. The calculator adjusts for the lower spread rate of exterior products on rough or porous surfaces and returns litres required per coat and in total.
Use CalculatorCalculate the number of wallpaper rolls required for any room. Enter room perimeter, ceiling height, and the wallpaper roll size. Specify the pattern repeat (straight match, drop match, or free match) and the calculator works out the number of usable drops per roll, total drops needed, and number of rolls to purchase including cutting waste.
Use CalculatorEstimate specialist coating quantities for primers, bonding agents, sealers, damp-proof coatings, and protective finishes on various substrates. Enter the surface area, substrate type, and number of coats. Returns total litres or kg required based on the typical spread rate for the selected coating type. Covers concrete, timber, and masonry substrates.
Use CalculatorBefore you build, make sure your project has the right consents in place.
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