Home & Energy Calculators

Material calculators are only useful if they answer in what the shop sells. A floor area in square metres does not tell you how many boxes of tiles to buy, so these work in packs, tins, bags and panels, include a waste allowance you can change, and round up -- because coming back for one more box is worse than having one spare.

Materials

The tile calculator, flooring calculator, paint calculator and wallpaper calculator cover interior work; the concrete calculator, gravel calculator, mulch and soil calculator and fence calculator cover outside. The paint calculator accounts for doors, windows and the number of coats, which is where most estimates go wrong.

Running costs

The electricity bill calculator turns an appliance's wattage and your tariff into a daily, monthly and yearly cost, which is the quickest way to find out what is actually expensive to run. The BTU calculator sizes heating and cooling for a room, and the solar panel calculator estimates output and payback from your own roof figures.

Journeys

The fuel cost calculator and trip cost calculator work out what a journey costs in fuel, split between passengers if you are sharing. Both work in either mpg or litres per 100 km, so it does not matter which your car reports.