Paint, Walls & Ceilings Calculators

Plan the finish of a room or an exterior wall before buying paint, primer, wallpaper or sealant. These calculators turn your measurements into coverage areas and material quantities, with allowances where the individual tool supports them. Start with wall area if you only know the room dimensions, then choose the calculator for your finish. Check the coverage printed on your chosen product, since surface texture, absorbency and the number of coats can change the amount needed. For trim details, use the caulk or board and batten tools. Each calculator explains its inputs, units and assumptions so you can adjust the estimate to your project.

Choose a calculator

• Board and Batten Spacing CalculatorLay out equal spaces between decorative battens with a batten at each end.Open calculator →
• Caulk CalculatorHow many 300 ml or 10.1 oz cartridges of caulk or silicone a joint needs.Open calculator →
• Exterior Paint CalculatorLitres or gallons of masonry or siding paint for a whole house, gables included.Open calculator →
• Paint CalculatorHow many litres or gallons of paint a room needs, minus doors and windows.Open calculator →
• Primer CalculatorLitres or gallons of primer for drywall, plaster, wood, metal or stain blocking.Open calculator →
• Wall Area CalculatorNet wall area, floor area, perimeter and volume of a room in m² or ft².Open calculator →
• Wallpaper CalculatorHow many rolls of wallpaper a room takes, counting drops, pattern repeat and openings.Open calculator →
• Wood Stain CalculatorLitres or gallons of deck stain, oil or fence treatment, adjusted for how thirsty the wood is.Open calculator →