Power Unit Converter

Convert power among five units

This power unit converter converts a numeric power value among watts (W), kilowatts (kW), megawatts (MW), mechanical horsepower (hp), and metric horsepower (hp metric). It uses watts as the common reference: the selected input is converted to watts, then from watts to the selected output unit. The result is a unit conversion, not a measurement of a motor or engine.

A watt is an SI unit of power. The two horsepower options are distinct: this converter uses 745.699872 W per mechanical hp and 735.49875 W per metric hp. Because the factors differ, the same watt value produces slightly different horsepower numbers depending on which definition you select.

Read the unit label before comparing

The label matters when reading an equipment specification. “Horsepower” can refer to more than one definition, while brake horsepower is not a separate option in this unit list. Check the source document’s convention before comparing ratings.

Follow the conversion through watts

For an input value x, first calculate its watt equivalent using the input unit’s factor. Then divide that watt value by the output unit’s factor. For example, 1,000 W ÷ 745.699872 gives about 1.341 mechanical hp; 1,000 W ÷ 735.49875 gives about 1.360 metric hp. The small difference is a definition difference, not a change in the underlying power amount.

Going in the other direction uses the same factors: 2 mechanical hp corresponds to 1,491.399744 W by the converter’s factor. Results may be rounded for display, so use the unrounded source measurement and the required precision for engineering or reporting work.

Choose the right kind of quantity

Power describes a rate of energy transfer. Energy accumulated over time is a different quantity: kilowatt-hours (kWh) are energy units and are not among the converter’s choices. For instance, a device’s power rating in kW and its energy use in kWh answer different questions; changing between them requires an elapsed time.

A conversion also cannot infer a machine’s actual output from its electrical input. Efficiency, operating conditions, and measurement method are outside this unit conversion. Use a rated or measured value when you need to describe real equipment performance.

Make a power conversion

1. Enter the known value

   Use the power amount from a label, specification, or calculation, keeping the original unit in view.

2. Select the input and output units

   Choose W, kW, MW, mechanical hp, or metric hp on each side. Check the horsepower definition explicitly.

3. Read and verify the result

   Use the displayed converted value and retain enough precision for your purpose. The worked factor can be checked by converting through watts.

Questions about horsepower and power

Use the result as a unit conversion

Displayed precision is arithmetic presentation; it does not establish how accurately the original equipment value was measured.

• The available units are W, kW, MW, mechanical hp, and metric hp. The converter does not label a brake-horsepower unit or convert energy units such as kWh.
• Check equipment documentation for the horsepower convention and whether its number is an input, shaft output, or another rated quantity.
• For design, safety, procurement, or compliance decisions, follow the equipment specifications and applicable measurement requirements.