Power Converter

About the Power Converter

Our free Power Converter converts between all major power units — watts, kilowatts, megawatts, horsepower, BTU per hour, and foot-pounds per second. Whether you're comparing engine specifications, sizing electrical equipment, or working on engineering calculations, this converter keeps the units aligned.

Power measures the rate at which energy is transferred or converted. The SI unit is the watt, but automotive and mechanical engineering commonly use horsepower, while HVAC systems use BTU per hour. This converter bridges all these measurement systems.

Enter your value, select units, and review the converted result. No formulas to look up, no manual math needed.

When This Page Helps

Power ratings are easy to misread when watts, kilowatts, horsepower, BTU per hour, and foot-pounds per second appear in the same project. This converter keeps the units aligned so you can compare equipment specs, check electrical loads, and reuse converted values without losing track of scale or conversion assumptions.

How to Use the Inputs

1. Select the power unit you are converting from.
2. Select the target power unit.
3. Enter the value to convert.
4. View the result below the inputs.
5. Swap units to reverse the conversion direction.

Example Calculation

Tips & Best Practices

• One mechanical horsepower equals approximately 745.7 watts.
• Electric motors are often rated in both kW and hp — use this converter to compare.
• BTU/hr is commonly used for HVAC system ratings in the United States.
• A typical household outlet provides about 1,800 watts (15 amps at 120 volts).
• Megawatts are used for large power plants and industrial installations.

Understanding Power Units

Power is the rate at which energy is used, produced, or transferred. Different industries use different units, making conversion essential for comparison and engineering calculations.

Horsepower vs. Kilowatts

The debate between horsepower and kilowatts is largely regional. North America favors horsepower for automotive applications, while Europe and most of the world use kilowatts. Both measure the same thing — the rate of doing work.

Practical Applications

Power conversions are crucial for comparing vehicle engines, sizing generators and solar systems, evaluating HVAC equipment, and understanding electrical loads. This converter simplifies all these tasks into a single, easy-to-use tool.

Frequently Asked Questions

• How many watts are in one horsepower?

  One mechanical horsepower equals approximately 745.7 watts. This is the standard conversion used in automotive and mechanical engineering. Electric horsepower is slightly different at exactly 746 watts.

• What is the difference between watts and kilowatts?

  One kilowatt equals 1,000 watts. Kilowatts are simply a more convenient unit for larger power values. Your home electricity usage is measured in kilowatt-hours, which combines power (kW) with time.

• How do I convert BTU/hr to watts?

  Multiply the BTU/hr value by 0.29307 to get watts. For example, 10,000 BTU/hr × 0.29307 = 2,930.7 watts or about 2.93 kW.

• What is a watt?

  A watt is the SI unit of power, defined as one joule per second. It measures the rate of energy transfer. Named after James Watt, it is used universally for electrical, mechanical, and thermal power measurements.

• Why do cars use horsepower instead of watts?

  Horsepower has been used in automotive engineering since the early days of the automobile. It originated from James Watt's comparison of steam engines to draft horses. While many countries now use kW in official specifications, horsepower remains popular in marketing and everyday use.

• How many watts does a typical household use?

  A typical US household uses about 1,200 watts on average (about 30 kWh per day). Peak usage can exceed 5,000–10,000 watts when major appliances like air conditioning, dryers, and ovens run simultaneously.