Electricity Cost Calculator

Every electrical appliance has a running cost, and it is simply its power consumption multiplied by the time it operates and the price of a unit of electricity. The multiplication is easy once you know two things: a kilowatt is a thousand watts, and a kilowatt-hour is one kilowatt running for one hour, which is the unit on an electricity bill. The power rating is printed on the appliance's label or rating plate, usually in watts or kilowatts. Some devices draw their rating continuously, like a heater or a light, while others cycle on and off, like a fridge or an oven, so the honest way to estimate the cost of a cycling appliance is to measure it with a plug-in energy monitor rather than trusting the plate. For continuously running loads, the calculation is direct: kilowatts times hours gives kilowatt-hours. Comparing appliances this way is genuinely useful. A device rated at 1,500 watts used two hours a day consumes about three kilowatt-hours daily, which at a typical tariff is a noticeable annual figure; a low-power alternative doing the same job can cost a fraction as much over a year. Standby loads deserve the same treatment, because an appliance that draws a few watts around the clock adds up to more than most people expect across a year. This calculator converts the rating and usage into kilowatt-hours per day, month and year, and prices them at your tariff. It assumes the appliance draws its rated power whenever it is on; find your actual tariff on a bill rather than using a national average, and use an energy monitor for anything that cycles. Running the numbers for a few large appliances often shows where the biggest savings lie.

This calculator returns estimates for planning and general information only. It is not engineering, architectural, structural, electrical or code advice, and it cannot replace a qualified professional who has seen the site. Material quantities depend on the actual dimensions, the product you buy and local building codes, so confirm the figures before ordering materials or starting work, and always follow local regulations.