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Power Converter

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Convert between watts, kilowatts, horsepower, and BTU per hour instantly.

Power Converter

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Converted value
0.1 kW

The formula

Result = Value x (watts per "From" unit) / (watts per "To" unit) 1 mechanical horsepower = 745.7 watts
Example

100 watts converts to 0.1 kW, or about 0.1341 horsepower, or roughly 341.21 BTU per hour.

Step-by-step guide

  1. Enter the value you want to convert.
  2. Choose the "from" and "to" units.
  3. Read the converted result.

Mechanical vs. electrical horsepower - a small but real difference

This converter uses mechanical horsepower (745.7 watts), the traditional definition based on historical steam-engine measurements and still standard for engines and motors. Electrical (or "metric") horsepower is defined slightly differently in some contexts (735.5 watts), a small but real difference that can matter for precise electrical engineering work - always check which definition a specific spec sheet is using if the exact figure matters.

Common mistakes

Confusing kW (power, a rate) with kWh (energy, power over time) - a 5kW device uses 5kWh of energy only if it runs for exactly one hour.
Using electrical horsepower's constant when a mechanical/engine horsepower figure is expected, or vice versa - the difference is small (about 1.4%) but can matter for precise work.

Frequently asked questions

How is power different from energy?

Power is a rate - how fast energy is used or produced, measured in watts. Energy is a total quantity, like kilowatt-hours or joules. See our Energy Converter for total energy conversions.

Why do car engines use horsepower while appliances use watts?

It's mostly historical and industry convention - horsepower dates back to comparisons with literal horse-drawn work in the early industrial era, while watts became the standard electrical unit as electricity became widespread. Both measure the same underlying quantity: power.

Why do air conditioners sometimes list BTU per hour instead of watts?

BTU per hour is the traditional unit for describing heating and cooling capacity in HVAC systems, particularly in the US - it directly ties to the historical BTU definition of heat energy rather than general electrical power.

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