Power Converter
This power converter lets you switch between six common power units in one step: watts (W), kilowatts (kW), megawatts (MW), mechanical horsepower (hp), BTU per hour (BTU/hr), and calories per second (cal/s). Power is the rate at which energy is transferred or work is done, and the same power level can look very different depending on the unit: one mechanical horsepower is 745.70 watts, 0.7457 kW, and 2,544.43 BTU/hr all at once. The watt is the SI unit of power and serves as this converter's internal reference: you pick any unit, enter a value, and the converter multiplies it by a fixed factor to get watts, then divides by each output factor to show all five remaining units simultaneously. Watts and kilowatts are used for electrical appliances, generators, and motors. Megawatts describe large power stations and industrial machinery. Horsepower is the standard rating unit for vehicle engines and legacy machinery in many markets. BTU per hour is common in heating, ventilation, and air conditioning in the United States. Calories per second appear in thermodynamics and laboratory contexts. You provide one value in any unit and receive all the equivalents instantly. The tool is useful for engineers comparing specifications, students working through thermodynamics problems, mechanics evaluating engine outputs, and building services professionals sizing HVAC equipment. All conversion factors are exact international definitions.
How it works
Each power unit has a fixed conversion factor to watts. The converter multiplies your input by that factor to get watts, then divides by each output factor to show all results at once. The factors used are: 1 kW = 1,000 W; 1 MW = 1,000,000 W; 1 hp (mechanical) = 745.69987 W; 1 BTU/hr = 0.29307107 W; 1 cal/s = 4.184 W. Because all factors are fixed constants, the conversion introduces no approximation beyond standard floating-point arithmetic.
Worked example
Starting from 1 hp: 1 times 745.70 gives 745.70 W and 0.7457 kW. Dividing 745.70 by 0.29307 gives 2,544.43 BTU/hr. Dividing by 4.184 gives 178.11 cal/s. These match the default values pre-filled in the converter above, so you can verify each output without changing anything.
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