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Built for Australian homes
How much paint, flooring or tiles do you actually need?
Free indoor calculators in square metres and litres — not guesswork. Work it out in seconds, order the right amount, avoid a second trip to Bunnings.
The calculators
Thirteen live calculatorsPaint coverage calculator
Litres of paint for any room. Handles walls, ceiling, doors and windows — with coats and waste margin.
FlooringFloor & tile calculator
Square metres, tile count and boxes for any room. Works with standard AU tile sizes and plank flooring.
BathroomsBathroom tile calculator
Tiles for walls, floor and shower recess. Subtract doors and windows. Includes grout and adhesive estimates.
WallsWallpaper rolls
Number of rolls for a room or feature wall, accounting for pattern repeat and door/window deductions.
WallsRender & plaster calculator
How many 20 kg bags for walls or ceilings. Single and two-coat systems for plaster, internal and external render.
ClimateAir con sizing
Recommended kW capacity for a room or open plan area — matched to AU climate zones.
ElectricalDownlights calculator
How many downlights for any room — based on AU lux standards and ceiling height. Includes grid spacing layout.
TilingGrout calculator
Kilograms of grout for any tiled surface — floor, wall, bathroom or benchtop. Any tile size and joint width.
TilingSplashback tile calculator
Tiles needed for a kitchen or bathroom splashback. Deducts rangehood and GPO cutouts. Mosaic, subway and standard sizes.
FinishingSkirting & cornice
Linear metres and number of lengths for skirting boards, cornice or both — with door deductions and waste margin.
ClimateInsulation batts calculator
How many batts for ceiling, walls or floor. Matched to Australian NCC climate zones with recommended R-values.
FlooringCarpet calculator
Linear metres of carpet for any room. Handles AU roll widths, pattern repeat, joins and multiple rooms.
FlooringUnderlay calculator
Rolls and m² of underlay for hybrid, laminate, timber or carpet flooring. Standard AU roll sizes.
Home renovation guides
Practical advice from a Queensland tradespersonHow much paint do you actually need for a room in Australia?
Coverage rates, AU tin sizes, feature walls and common mistakes — before you buy.
BathroomsHow to tile a bathroom in Australia — what to order and what not to skimp on
Tile quantities, waste margins, waterproofing, grout and adhesive — the full picture.
CoolingChoosing the right air conditioner size for Australian homes
kW ratings, room size, climate zones and why bigger isn't always better.
Free tools. Zero fluff.
Metric-first, always
Every calculator uses square metres, litres and millimetres — the units on the tin, the box and the invoice.
No sign-up, no email
Type your numbers in. Get your answer. Leave. We don't want your email and we're not sending a newsletter.
Phone-friendly
Built for standing in a room with a tape measure in one hand. Big inputs, clear outputs, no pinch-to-zoom.
Honest waste margins
Every result adds a sensible waste margin and explains why. Order enough the first time.