How much does it cost to run a 1,000-watt appliance?

A 1,000 W (1 kW) appliance uses 1 kWh per hour. Running it 1 hour a day for 30 days uses 30 kWh, which costs 30 × your price per kWh — about US$5.50 at the US average of 18.34 cents.

How do I convert watts to kWh?

Multiply watts by hours of use and divide by 1,000. A 60 W laptop used 6 hours a day uses 0.36 kWh per day, or about 10.8 kWh in a 30-day month.

Why is my bill higher than the calculator result?

Bills add fixed daily or monthly charges, and many tariffs have tiers, time-of-use pricing or local taxes. The calculator shows the usage cost of the appliances you list, so enter the unit rate from your own bill for the closest result.

Electricity Cost Calculator

Add your appliances, pick a country and see the kWh and running cost per day, month and year. Override the price with the rate from your own bill.

1. Appliances and usage

Appliance	Power (W)	Hours per day	Days per month	Qty	kWh / month

Use the rated power on the label or in the manual. Fridges, freezers and air conditioners cycle on and off, so the presets use average running power. If your fridge label shows kWh per year, divide it by 8.76 to get average watts.

2. Electricity price

Country

Price per kWh

How to calculate electricity cost

Energy (kWh) = power (W) × hours per day × days ÷ 1,000. Cost = kWh × price per kWh. For example, a 1,000 W heater used 1 hour a day for 30 days uses 30 kWh; at US$0.18 per kWh that is about US$5.40 a month.

The default prices are typical all-in household rates (energy plus taxes where the source includes them) and do not include fixed daily or monthly charges. Your own rate can be very different by state, province, supplier, plan or time of day, so type the unit rate from your bill into the price box to override it.

South Korea uses a progressive tariff: the price per kWh depends on the household's total monthly use. With the KEPCO option on, the calculator works out the bill with and without your appliances (tiers 120.0 / 214.6 / 307.3 won per kWh, climate charge 9.0 won, Q4 2026 fuel adjustment +5.0 won, 10% VAT and the 2.7% power fund) and shows the difference.

Default prices and sources

US-dollar equivalents use ECB euro reference rates of 30 October 2026. GlobalPetrolPrices figures are household averages for 2023–2025 (Q4 2025 update), converted from US dollars at the same rates.

Frequently asked questions

How much does it cost to run a 1,000-watt appliance?: A 1,000 W (1 kW) appliance uses 1 kWh per hour. Running it 1 hour a day for 30 days uses 30 kWh, which costs 30 × your price per kWh — about US$5.50 at the US average of 18.34 cents.
How do I convert watts to kWh?: Multiply watts by hours of use and divide by 1,000. A 60 W laptop used 6 hours a day uses 0.36 kWh per day, or about 10.8 kWh in a 30-day month.
Why is my bill higher than the calculator result?: Bills add fixed daily or monthly charges, and many tariffs have tiers, time-of-use pricing or local taxes. The calculator shows the usage cost of the appliances you list, so enter the unit rate from your own bill for the closest result.