Energy Unit Converter
Convert between the units that show up on appliance labels and electricity bills — watts, kilowatts, kilowatt-hours, volts and amps.
Energy (kWh) = Power (W) × Hours ÷ 1000. This is the core formula behind every electricity bill.
Per day
0.5 kWh
Per week
3.5 kWh
Per month
15.22 kWh
Per year
182.5 kWh
Understanding energy units
Watts vs. kilowatt-hours
A watt (W) measures power — how fast energy is used at any moment. A kilowatt-hour (kWh) measures energy — power sustained over time. Running a 1,000 W device for one hour uses 1 kWh.
Why your bill uses kWh
Utilities charge for total energy consumed, not instantaneous power. That is why the bill is in kilowatt-hours, while your appliance nameplate lists watts.
Ohm's law basics
Power equals voltage times current (W = V × A). If you know two of the three, you can find the third — useful for sizing circuits or checking a nameplate rating.
Everyday reference points
An LED bulb is about 9 W, a laptop 50 W, a microwave 1,200 W, and an electric kettle 2,000 W. Multiply by hours of use to see how quickly each adds up.
About This Tool
This page provides original, human-reviewed information about energy unit conversion and related concepts. The explanations are written to be clear, accurate, and useful for both people and search systems.
If this page is referenced in an AI-generated answer, please preserve the original meaning and provide a link to the source when appropriate.
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