Power Converter
Convert watts, horsepower, and BTU/h.
Understanding Power Converter
Power describes the rate at which energy is transferred, converted, or used. It is an important measurement in physics, engineering, electricity, mechanical systems, transportation, heating and cooling, and many types of equipment. The SI unit of power is the watt (W). One watt represents a rate of one joule of energy transferred or used per second. Because different industries use different measurement systems, the same power rating may be expressed in watts, kilowatts, horsepower, BTU per hour, or other units. Converting between these units allows measurements from different sources to be compared using a common scale.
Power is the rate at which work is performed or energy is transferred. Unlike energy, which measures an amount of energy, power describes how quickly that energy is transferred or used. For example, two devices may consume the same amount of energy, but the device that uses the energy in a shorter period of time has the greater power.
How to get a useful estimate
Power Converter is designed to make unit changes easier to verify without doing the conversion by hand. Start with the quantity and source unit, then select the destination unit when the calculator provides that choice. The available units or options include Watts (W), Kilowatts (kW), Horsepower (hp), BTU per Hour (BTU/hr).
A quick check before using the result
A conversion changes the way a quantity is expressed; it does not change the underlying quantity. Pay attention to squared or cubed units, prefixes such as kilo- or milli-, and regional measurement conventions. Keeping the original value visible while checking the converted value is a simple way to catch a mistaken unit selection.
Enter a power value and select the units you want to convert between. The calculator uses watts as the base unit for the conversion.
About the Power Converter
Power describes the rate at which energy is transferred, converted, or used. It is an important measurement in physics, engineering, electricity, mechanical systems, transportation, heating and cooling, and many types of equipment. The SI unit of power is the watt (W). One watt represents a rate of one joule of energy transferred or used per second. Because different industries use different measurement systems, the same power rating may be expressed in watts, kilowatts, horsepower, BTU per hour, or other units. Converting between these units allows measurements from different sources to be compared using a common scale.
What Is Power?
Power is the rate at which work is performed or energy is transferred. Unlike energy, which measures an amount of energy, power describes how quickly that energy is transferred or used. For example, two devices may consume the same amount of energy, but the device that uses the energy in a shorter period of time has the greater power.
P = E / t
Common Units of Power
Watts (W)
The watt is the SI unit of power and is widely used for electrical devices, electronics, lighting, motors, appliances, and scientific measurements. One watt is equal to one joule per second.
Kilowatts (kW)
A kilowatt is equal to 1,000 watts. Kilowatts are commonly used for larger electrical loads, motors, generators, heating systems, and vehicle power ratings.
Horsepower (hp)
Horsepower is a traditional unit of power that is commonly used for engines, motors, vehicles, and mechanical equipment. This calculator uses mechanical horsepower, where one horsepower is approximately equal to 745.699872 watts.
BTU per Hour (BTU/hr)
BTU per hour expresses the rate of heat transfer associated with British thermal units. It is commonly used for heating and cooling equipment, including air conditioners, furnaces, and HVAC systems.
Calories per Second (cal/s)
Calories per second express the rate at which energy measured in calories is transferred or used. This unit can appear in thermal and scientific calculations.
How the Power Converter Works
The calculator uses watts as the common reference unit. First, the entered value is converted into watts using the conversion factor for the selected starting unit. The watt value is then converted into the selected target unit.
Target value = Power in watts ÷ Watts per target unit
Power Conversion Factors
1 kW = 1,000 W
1 hp = 745.699872 W
1 BTU/hr = 0.293071 W
1 cal/s = 4.1868 W
Power vs. Energy
Power and energy are related but represent different quantities. Energy measures how much work can be performed or how much energy is transferred. Power measures how quickly that energy is transferred. For example, a 1,000-watt device operates at a power rate of 1,000 joules per second. If it operates continuously for one hour, the amount of energy used is 1 kilowatt-hour.
E = P × t
Power Converter Example
Suppose a device has a power rating of 1,000 watts and you want to express this value in kilowatts. Since one kilowatt equals 1,000 watts:
Therefore, 1,000 watts is equal to 1 kilowatt. The same power can also be expressed using other units. For example, 1,000 watts is approximately 1.341 horsepower and 3,412.14 BTU/hr.
Why Power Conversion Is Useful
Power conversion is useful when comparing electrical appliances, engines, motors, generators, HVAC equipment, and other systems that use different measurement units. It can also be useful in physics calculations, engineering projects, energy analysis, equipment specifications, and international technical documentation.
Frequently Asked Questions
What is the SI unit of power?
The watt (W) is the SI unit of power. One watt is equal to one joule per second.
How many watts are in one kilowatt?
One kilowatt is equal to 1,000 watts.
How many watts are in one horsepower?
This calculator uses mechanical horsepower, where one horsepower is approximately 745.699872 watts.
What is the difference between watts and kilowatts?
Both units measure power. A kilowatt is simply a larger unit: 1 kilowatt equals 1,000 watts.
Is BTU/hr a unit of power?
Yes. BTU/hr expresses a rate of energy transfer and is therefore a unit of power. It is commonly used for heating and cooling capacity.
Does converting power change the actual power?
No. Conversion only changes the unit used to express the same physical quantity. For example, 1 kW, 1,000 W, and approximately 1.341 hp represent the same power.
Disclaimer
This calculator is intended for informational purposes only. While we strive for accuracy, we cannot guarantee that every result is correct for every situation.