Power Converter

Convert Watts, Kilowatts, Megawatts, Milliwatts, Horsepower, BTU/h, Calories/s & More

Free online power converter for all common units. Instantly convert between watts, kilowatts, megawatts, milliwatts, horsepower, BTU per hour, calories per second, and more.

What is a Power Converter?

A power converter is a tool that allows you to quickly and accurately convert between different units of power, such as watts, kilowatts, megawatts, milliwatts, horsepower (metric, mechanical, electric), BTU per hour, calories per second, and more. This is essential for science, engineering, energy, and everyday life when working with different measurement systems.

Supported Power Units

  • Watt (W): The SI unit of power. Used worldwide in science and engineering.
  • Kilowatt (kW): 1,000 watts. Used for household appliances and engines.
  • Megawatt (MW): 1,000,000 watts. Used for power plants and large-scale energy.
  • Milliwatt (mW): 1/1,000 of a watt. Used for small electronics and lasers.
  • Horsepower (metric): 735.49875 watts. Used in Europe and Asia for engines.
  • Horsepower (mechanical): 745.699872 watts. Used in the US and UK for engines.
  • Horsepower (electric): 746 watts. Used for electric motors.
  • BTU per hour (BTU/h): 0.29307107 watts. Used for heating and air conditioning.
  • Calorie per second (cal/s): 4.184 watts. Used in chemistry and nutrition.
  • Kilocalorie per hour (kcal/h): 1.16222222 watts. Used in nutrition and exercise.
  • Foot-pound per second (ft·lb/s): 1.35581795 watts. Used in engineering.

How to Use the Power Converter

  1. Enter the value you want to convert.
  2. Select the unit you are converting from.
  3. View instant conversions to all other supported units below.

Why Use ManyCalcs Power Converter?

  • Completely free and ad-free.
  • Supports all major power units.
  • Instant, accurate, and easy-to-use interface.
  • Mobile-friendly and accessible on any device.
  • Educational content for every unit.

Frequently Asked Questions

How do I convert watts to horsepower?
Enter the value in watts, select "Watt (W)", and view the result in horsepower in the output list.
What is the difference between metric and mechanical horsepower?
Metric horsepower is 735.49875 W, mechanical (US/UK) is 745.699872 W, and electric is 746 W.
What is a BTU per hour?
BTU/h is used for heating and air conditioning. 1 BTU/h = 0.29307107 W.
Is this power converter free?
Yes, the ManyCalcs power converter is 100% free and always will be.

For more information, see Units of power on Wikipedia.

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