Power Converter
Convert power units quickly and accurately with the free Smart Unit Calc Power Converter. Convert watts (W), kilowatts (kW), megawatts (MW), horsepower (hp), BTU per hour, foot-pounds per second, refrigeration tons and other common power measurements.
Power Conversion Calculator
What Is Power?
Power is the rate at which energy is transferred, converted or used. It describes how quickly work is performed or energy is delivered. Power is commonly used in electrical systems, engines, motors, generators, heating systems, mechanical equipment and industrial machinery.
The watt (W) is the SI unit of power. One watt is equal to one joule of energy transferred per second.
Other common power units include kilowatts, megawatts, gigawatts, horsepower, BTU per hour, foot-pounds per second and refrigeration tons.
Power Units Supported by This Converter
| Power Unit | Symbol | Equivalent in Watts |
|---|---|---|
| Watt | W | 1 W |
| Microwatt | µW | 0.000001 W |
| Milliwatt | mW | 0.001 W |
| Kilowatt | kW | 1,000 W |
| Megawatt | MW | 1,000,000 W |
| Gigawatt | GW | 1,000,000,000 W |
| Terawatt | TW | 1,000,000,000,000 W |
| Mechanical Horsepower | hp | 745.699872 W |
| Metric Horsepower | PS | 735.49875 W |
| Boiler Horsepower | boiler hp | 9,809.5 W |
| BTU per Hour | BTU/h | 0.2930710702 W |
| Foot-pound force per Second | ft·lbf/s | 1.355817948 W |
| Foot-poundal per Second | ft·pdl/s | 0.04214011009 W |
| Kilocalorie per Hour | kcal/h | 1.162222222 W |
| Calorie per Second | cal/s | 4.184 W |
| Ton of Refrigeration | TR | 3,516.852842 W |
Watt Converter
The watt is the standard SI unit for measuring power. It is commonly used for electrical devices, motors, lighting, appliances and scientific calculations.
Common watt conversions include:
- 1 kW = 1,000 W
- 1 MW = 1,000,000 W
- 1 GW = 1,000,000,000 W
- 1 mechanical hp ≈ 745.699872 W
- 1 BTU/h ≈ 0.293071 W
Kilowatt (kW) Converter
Kilowatts are widely used for electrical equipment, motors, generators, solar systems, air conditioners, pumps, heaters and household appliances.
For example, a 5 kW electrical heater has a power rating of 5,000 watts.
Megawatt (MW) Converter
Megawatts are commonly used for large electrical generators, power plants, solar farms, wind farms and industrial facilities.
Large power generation projects may also be described in gigawatts.
Horsepower Converter
Horsepower is a traditional unit of power commonly associated with engines, vehicles, pumps, compressors and mechanical equipment.
Mechanical Horsepower
Therefore:
Metric Horsepower
Metric horsepower, often represented as PS or CV depending on the market, is different from mechanical horsepower.
BTU per Hour Converter
BTU per hour (BTU/h or BTU/hr) is a unit of power commonly used for heating, ventilation, air conditioning and thermal equipment.
This means:
10,000 BTU/h ≈ 2.93071 kW
BTU/h measures power, while BTU by itself measures energy.
Refrigeration Ton to kW and Watts
A ton of refrigeration is a traditional HVAC capacity unit used to describe cooling capacity.
Using the standard refrigeration conversion:
1 TR ≈ 3.51685 kW
Refrigeration ton is a measure of cooling capacity and should not automatically be interpreted as electrical input power. Actual electrical consumption depends on equipment efficiency.
Power Conversion Formulas
Basic Power Formula
Where P is power, E is energy and t is time.
Electrical Power
For DC circuits, electrical power can be calculated from voltage multiplied by current.
AC Electrical Power
For single-phase AC systems, real power depends on voltage, current and power factor. Three-phase systems use additional factors based on the electrical configuration.
Mechanical Power
Mechanical power can be calculated by multiplying force by velocity.
Common Power Conversion Chart
| Power | Equivalent |
|---|---|
| 1 W | 1 W |
| 1 kW | 1,000 W |
| 1 MW | 1,000 kW |
| 1 GW | 1,000 MW |
| 1 mechanical hp | 745.699872 W |
| 1 metric hp | 735.49875 W |
| 1 BTU/h | ≈ 0.293071 W |
| 1 kW | ≈ 3,412.14 BTU/h |
| 1 refrigeration ton | ≈ 3.51685 kW |
| 1 kW | ≈ 1.34102 mechanical hp |
Power Conversion Examples
Convert 5 kW to Watts
Therefore, 5 kW = 5,000 W.
Convert 100 HP to kW
Therefore, 100 mechanical horsepower is approximately 74.57 kW.
Convert 10 kW to Horsepower
Therefore, 10 kW ≈ 13.41 mechanical hp.
Convert 12,000 BTU/h to kW
Therefore, 12,000 BTU/h is approximately 3.51685 kW.
Convert 1 MW to kW
Power vs Energy
Power and energy are related but represent different quantities.
| Quantity | What It Measures | Common Units |
|---|---|---|
| Power | Rate of energy transfer or use | W, kW, MW, hp, BTU/h |
| Energy | Total amount of work or energy transferred | J, kJ, MJ, Wh, kWh, BTU |
For example, a 2 kW appliance operating for 5 hours uses:
Energy = 2 kW × 5 h
Energy = 10 kWh
To convert energy units, use our Energy Converter.
Where Power Conversion Is Used
Electrical Engineering
Power conversion is used for electrical loads, motors, generators, transformers, batteries, solar systems, electrical panels and power distribution.
Automotive Engineering
Vehicle engine and motor ratings are frequently expressed in horsepower or kilowatts. Converting between hp and kW makes it easier to compare vehicle specifications from different countries.
HVAC
Air conditioners, chillers, heaters and refrigeration systems can use BTU/h, refrigeration tons and kilowatts to describe thermal capacity or power.
Industrial Equipment
Pumps, compressors, motors, turbines and generators commonly use watts, kilowatts, megawatts or horsepower.
Renewable Energy
Solar panels and photovoltaic systems are commonly rated in watts, kilowatts or megawatts depending on system size.
Science and Engineering
Scientists and engineers use watts as the SI unit of power and may encounter other units when working with international or legacy specifications.
How to Use the Power Converter
- Enter the power value.
- Select the original power unit.
- Select the unit you want to convert to.
- Click Convert.
- Use Copy Result to copy the answer.
- Use Swap Units to reverse the conversion.
The calculator also updates automatically when the value or units are changed.
Power Conversion Accuracy
The calculator uses the watt as its base unit and converts each supported unit through its corresponding power factor. This provides consistent results across metric, imperial and specialized power units.
About dBm and dBW
dBm and dBW are logarithmic power-level units rather than ordinary linear power units like watts or kilowatts. They therefore require a different mathematical conversion method.
dBW = 10 × log10(P / 1 W)
For this reason, dBm and dBW should not be placed into the same simple multiplier table as watts, horsepower or kilowatts.
A dedicated RF and logarithmic power calculator can be added later if your website targets telecommunications, radio-frequency, antenna and signal-strength searches.
Frequently Asked Questions About Power Conversion
Related Unit Converters
Popular Power Conversion Searches
This Power Converter is designed for common searches including watts to kilowatts, kilowatts to watts, watts to horsepower, horsepower to watts, hp to kW, kW to hp, megawatts to kilowatts, kilowatts to megawatts, watts to BTU/h, BTU/h to watts, kW to BTU/h, BTU/h to kW, horsepower converter, mechanical horsepower converter, metric horsepower converter, refrigeration ton converter and kilocalories per hour to watts.
It can be used for electrical engineering, motors, generators, vehicles, HVAC systems, refrigeration, solar power, industrial machinery, mechanical engineering and scientific calculations.