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Estimate appliance energy use and cost from wattage, hours per day, days, quantity, and the electricity rate you enter.
Results update as you type. No calculate button. All calculations run locally in your browser.
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Bars are scaled to the larger cost. The full-year bar assumes the same daily use every day; it is a projection, not a bill forecast.
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Same wattage, hours, rate and quantity; only the number of days changes. The rate you enter is used throughout — tiered or time-of-use pricing is not modelled.
Energy (kWh) = watts ÷ 1,000 × hours per day × days × device count. Cost = energy × price per kWh.
Power 1,500 W, 4 hours per day, 30 days, 1 device, rate 0.80 per kWh (an example rate you replace with your own): daily energy = 1,500 ÷ 1,000 × 4 = 6 kWh, so period energy = 6 × 30 = 180 kWh and cost = 180.00 × 0.80 = 144.00. Daily cost is 4.80. The rate here is only the example default — your bill's actual rate is what matters.
Standby power, duty cycles (appliances that cycle on and off), tiered rates, taxes, demand charges and time-of-use pricing are not modelled: a single flat rate is applied to all energy. If your appliance cycles, enter its average power draw, not its peak wattage. No rate is presented as a market average — the default rate is an example to replace.
Cost = watts ÷ 1,000 × hours per day × days × device count × price per kWh. A kilowatt-hour (kWh) is 1,000 watts used for one hour.
The per-kWh price from your own bill or tariff, including only what you want the estimate to cover. If your bill adds taxes or fixed charges separately, this estimate will not match the bill total.
Standby draw is not included unless you add it: either add standby watts to the power input for the hours the device is plugged in, or run a second calculation for standby use.
Its average draw over the hours you enter, not the peak wattage on the label. A fridge rated at 150 W may average far less across a day.
Tiered rates, time-of-use pricing, fixed daily charges, taxes and other appliances on the same bill all sit outside this single-appliance calculation.
No. This calculation runs locally in your browser and the values you enter are not sent to a CalcMintly database.
Results are estimates only and do not constitute professional advice.