About

Every calculator on this site performs a real calculation from a documented formula. There are no placeholder results and no invented prices: where a cost estimate is shown, it comes from a price you enter yourself.

What this site covers

All 10 phases are complete — 100 calculators in total: flooring and tiles, concrete and construction, painting and walls, garden and landscaping, roofing and exterior, home renovation and cost, measurements and conversions, plumbing and water, electrical and energy, and doors, windows and interior. There is also a calculator directory with search, filters and sorting, plus 36 step-by-step DIY guides.

Who it is for

Homeowners in the United States, the United Kingdom and Australia. Every calculator works in both imperial units (feet, inches, square feet) and metric units (metres, millimetres, square metres), and switches between the two without re-entering your measurements.

Accuracy

Formulas are shown on each calculator page with a worked example you can check by hand. Material quantities are always rounded up — you cannot buy part of a tile, plank or bag — and wastage allowances are applied before rounding, never after.

No guarantees

Calculators estimate material quantities. They do not replace a professional survey, and they do not guarantee a price, a result, or that a material is suitable for your specific project. Always check the manufacturer's instructions for the product you buy.