Power Converter

Convert one power rate into another

Enter a finite value and select source and destination units. The calculator converts through watts and labels mechanical horsepower and BTU per hour explicitly so unlike meanings are not hidden.

Power is a rate

Power describes how quickly energy is transferred or used. One watt is one joule per second. A kilowatt is 1,000 watts, and a megawatt is 1,000,000 watts. Power differs from energy: a 2-kilowatt device running for three hours uses 6 kilowatt-hours of energy.

Horsepower needs a definition

This page uses mechanical horsepower, approximately 745.699872 watts. Metric horsepower and electrical horsepower use different conventions. A label that says only “hp” can therefore be ambiguous. Match the definition used by the equipment specification or standard you are reading.

BTU per hour

BTU per hour is a power rate often used for heating and cooling capacity. This calculator uses 1 BTU/h as approximately 0.29307107 watts. A BTU by itself is energy, while BTU/h is energy per time. Omitting “per hour” changes the physical quantity.

Worked example

Convert 10 kilowatts to mechanical horsepower. Ten kilowatts equals 10,000 watts. Dividing by 745.699872 gives about 13.4102 mechanical horsepower. The arithmetic does not mean a real motor rated 10 kW will deliver that shaft output under every condition.

Input signs and precision

Negative values are accepted because signed power can describe direction in engineering calculations, such as export versus import. Results show up to twelve significant digits. Displayed rounding and JavaScript floating-point arithmetic make the output practical conversion data, not arbitrary-precision metrology.

Limitations and equipment cautions

This page converts units only. It does not calculate energy cost, motor efficiency, electrical current, voltage, phase, power factor, heat loss, duty cycle, starting load, or safe equipment capacity. Nameplate values can refer to input, output, peak, nominal, or rated conditions; preserve that context.

Power Converter FAQ

Is kW the same as kWh?

No. kW is power; kWh is energy accumulated over time.

Which horsepower does this use?

Mechanical horsepower at approximately 745.699872 watts.

Can this size a generator?

No. Generator sizing requires load behavior, starting demand, power factor, and qualified guidance.