Power is the rate at which work is done or energy is transferred, and it answers a question that raw energy alone cannot: not just how much was achieved, but how quickly. Two engines can do the same amount of work, lifting the same load to the same height, yet one may finish in a second and the other in a minute. The fast one is more powerful. This calculator turns that idea into a number. Enter the work or energy in joules and the time taken in seconds, and it returns the power in watts, kilowatts and mechanical horsepower, so you can read it on the scale that fits the job. The core relationship could not be simpler: power equals work divided by time. One watt is one joule delivered every second, which makes the watt a natural unit for everything from a light bulb to a hydro turbine. Because real machines span such a wide range, the calculator also gives kilowatts for larger outputs and horsepower for engines and motors, using the mechanical horsepower of 745.6999 watts. There is a second, equally useful form worth keeping in mind. When a constant force moves an object at a steady speed, power also equals force multiplied by velocity, written P = F v. That version is handy when you know the push and the speed rather than the total work and the clock time, and the two forms always agree. Time cannot be zero, since dividing by zero has no meaning, so the calculator guards against it. It is built for students, teachers, engineers and anyone comparing how fast energy is being used or delivered.
Power is the work done or energy transferred divided by the time taken. The result is in watts when work is in joules and time is in seconds. One watt is one joule per second.
P = W / t
P = F × v (alternative form for a force at a steady speed)
1 hp = 745.6999 W · 1 kW = 1,000 W
A machine does 500 joules of work in 10 seconds. The power is 500 / 10 = 50 watts, which is 0.05 kilowatts. Dividing by 745.6999 gives about 0.0670 mechanical horsepower.
This calculator is for students, teachers, engineers and anyone working out how quickly work is done or energy is transferred.
Power is the work done or energy transferred divided by the time taken, P = W / t. With work in joules and time in seconds the result is in watts, where one watt is one joule per second.
Divide the power in watts by 745.6999 to get mechanical horsepower. So 50 watts is about 0.067 horsepower, and one horsepower is roughly 745.7 watts.
When a constant force moves an object at a steady speed, power also equals the force multiplied by the velocity, P = F v. It is useful when you know the push and the speed rather than the total work and time.
One kilowatt is one thousand watts. To convert watts to kilowatts, divide by 1,000.
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