About WhatItCosts

WhatItCosts is a set of free calculators that show what your appliances cost to run. Enter the power an appliance uses, how long you run it and your electricity price, and you get the energy and the cost per hour, day, week, month and year.

How accurate is it?

The maths is exact, but the answer is only as good as the numbers you put in. The typical wattages on each page are averages for common models. Your appliance may use more or less. The most accurate way to find out is a plug-in power meter, or the figure on the appliance label.

For appliances that cycle on and off, such as fridges, heaters and air conditioners, use the "time at full power" setting. We give a sensible starting value for each one.

Your privacy

The calculators run in your browser. The numbers you type are not sent to us. See the privacy policy for details.

Found a mistake?

If a typical wattage looks wrong or something is unclear, please tell us.