Make sense of your energy use, one calculation at a time.
From a kettle to an electric car, find out what your electricity use could cost. Use your own UK tariff, compare options and see the assumptions behind every estimate.
Electricity cost calculator
Calculate an appliance’s electricity use and running cost per day, month and year using its power, operating schedule and your unit rate.
CalculateAll tools
Electricity cost calculator
Calculate an appliance’s electricity use and running cost per day, month and year using its power, operating schedule and your unit rate.
Appliance running cost calculator
Explore editable appliance examples and estimate electricity use with the actual power and operating hours of your own equipment.
Compare appliance energy costs
Compare two appliances or operating scenarios and see their electricity use, annual costs, cash savings and percentage difference.
Standby electricity calculator
Estimate the monthly and annual electricity cost of devices left in standby using measured watts, standby hours and device count.
Solar and home battery calculator
Estimate solar generation, household coverage, energy savings and simple payback, with an optional domestic battery scenario.
Heat pump electricity and cost calculator
Estimate heat pump electricity use from annual heat demand and SCOP, then compare running costs with direct electric or gas heating.
Electric vehicle charging cost calculator
Calculate battery energy, electricity drawn from the grid and the cost of charging between two battery percentages.
Electric vehicle cost per distance
Estimate an electric vehicle’s energy cost for a journey, per 100 km, and across your monthly and annual mileage.
Electric car versus petrol or diesel costs
Compare annual electricity and fuel costs for the same driving distance using your consumption figures and local energy prices.
Household electricity use calculator
Review annual household electricity use, monthly averages, consumption per person and per square metre, and the effect of a tariff change.
Energy units and percentage calculator
Convert W and kW or Wh and kWh, and calculate percentage changes without confusing electrical power with energy consumption.
For a UK appliance calculation, use the unit rate in pence per kWh from your tariff and convert it to pounds. Keep any daily standing charge separate: using the kettle less does not usually remove that charge. A monthly Direct Debit is a payment towards your account, so it should not be treated as your measured electricity use for that month.
A tumble dryer comparison is most useful when both options dry the same amount of laundry. For a fridge-freezer, use its energy label or measured kWh rather than assuming its compressor draws full power all day. If you charge an electric car on a time-of-use tariff, calculate the charging sessions at the relevant rate and include charging losses.