Free, no-signup home calculators: paint, flooring, tile, BTU and budget. Open the tools →
The instrument drawer

Free home tools that do the maths

Every calculator here is built in-house, tested against real projects and free to use. Nothing is stored, and no email is required.

Paint & Colour

Paint Calculator

Work out gallons of paint and primer for any room, including doors and windows.

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Wallpaper Calculator

Rolls of wallpaper needed, accounting for pattern repeat.

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Flooring

Flooring Calculator

Boxes of flooring needed for any room, with a waste allowance for cuts and pattern.

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Tiling

Tile Calculator

Tiles, grout and adhesive for floors or walls, with breakage allowance.

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Energy

AC & Heating BTU Calculator

Estimate the cooling capacity a room actually needs.

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Appliance Running Cost Calculator

What any appliance costs to run per day, month and year.

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Insulation R-Value Calculator

Check assembly R-value and the insulation depth needed to hit a target.

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Costs

Renovation Budget Calculator

Build a realistic project budget with labour split and contingency.

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Mortgage Payment Calculator

Monthly payment, total interest and payoff figures for a home loan.

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Measuring

Room Size & Volume Calculator

Area, perimeter, volume and metric conversions for any rectangular room.

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Outdoor

Concrete Calculator

Cubic yards of concrete for a slab, patio or path, plus bag counts.

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Lawn Seed & Fertiliser Calculator

Grass seed and fertiliser quantities for new lawns or overseeding.

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