電費計算機

How to use this calculator

1. Enter the appliance power and choose the unit (watts or kW).
2. Enter the hours of use per day.
3. Enter your price per kWh and currency symbol.
4. Click Calculate for the cost per day, month and year.

How the cost is calculated

A device's power in watts divided by 1000 gives kilowatts (kW). Multiply by the hours it runs to get kilowatt-hours (kWh), the unit your utility bills you in. Multiply kWh by your tariff to get the cost.

Example

A 100 W bulb running 5 hours a day uses 0.5 kWh per day. At $0.15/kWh that is about $0.075 per day, roughly $2.28 per month and $27.38 per year.

Typical appliance wattages

常見問題

How do I calculate my electricity cost?

Energy (kWh) = power in kW × hours used; cost = energy × your price per kWh. Watts ÷ 1000 gives kW.

How much does it cost to run a 1500 W heater?

It uses 1.5 kWh per hour. At $0.15/kWh that is about $0.23 per hour, or roughly $1.13 for 5 hours a day.

What is a kWh?

A kilowatt-hour is the energy used by a 1000 W appliance running for one hour — the unit your utility bills you in.