Power Converter
Convert between watts, kilowatts, horsepower, BTU/hr, and more
What is the Power Converter?
A power converter switches between units that measure the rate of energy use or transfer, watts, kilowatts, megawatts, horsepower, BTU per hour, and foot-pounds per second. You'll see these units when comparing car engine specs (horsepower), checking appliance energy consumption (watts), looking at generator capacity (kilowatts), or reading utility data (megawatts). CalciHub's power converter handles all standard units so you can quickly understand what any power figure actually means.
How Does It Work?
The watt (W) is the SI base unit for power. All other units convert to and from it using fixed ratios.
Formula:
Converted Power = Input Power × Conversion Factor
Common conversion factors:
1 kilowatt (kW) = 1,000 watts
1 horsepower (hp) = 745.7 watts
1 megawatt (MW) = 1,000,000 watts
1 BTU/hour = 0.293071 watts
Input Power: the value you want to convert
Conversion Factor: the fixed ratio between the two units
How to Use CalciHub's Power Converter
1. Enter the power value in the input field.
2. Select the unit you're converting from (e.g., horsepower, watts, kilowatts).
3. Select the unit you want the result in.
4. The converted figure appears right away.
Tip: When comparing appliances for energy efficiency, convert everything to watts so you can directly compare consumption, don't try to compare watts to horsepower mentally.
A Quick Example
A mechanic is checking whether a car's 180-horsepower engine translates to a competitive kilowatt rating for a European market where kW is the standard spec.
Input: 180 horsepower
Converting to kilowatts
180 × 0.7457 = 134.2 kW
Output: 134.2 kW
That figure can now be directly compared to European spec sheets. For the same car, European listings use kW, knowing the conversion keeps you from underselling or misreading what an engine actually delivers.
Frequently Asked Questions
A watt is one joule of energy used per second. A 60W light bulb uses 60 joules every second. It's the standard unit for power in most scientific and engineering contexts.
Horsepower became the standard in the late 18th century when James Watt wanted to compare steam engine output to the work a horse could do. The term stuck in the US and UK automotive industries, though Europe now formally uses kilowatts on vehicle registrations.
A typical home uses several kilowatts at peak times and averages around 1–1.5 kW continuously. Monthly usage on your electricity bill is measured in kilowatt-hours (kWh), not watts, because watts only describes the rate, not the total amount consumed.
A megawatt (MW) is one million watts — enough to power roughly 400–600 average homes. A gigawatt (GW) is one billion watts. These units show up in discussions about power plants, grid capacity, and large-scale solar or wind installations.
Yes, completely free – no account needed, and no usage limits.
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