HP to kW

Welcome to hp to kW, our website about the conversion of horsepower to kilowatts.

Horsepower measure power, the rate of doing work.

However, there are different definitions of the unit hp depending on the context of use as well as geographical location, the most prominent of which are mechanical horsepower hp(I), aka imperial horsepower, and metric horsepower hp(M), also known as, for instance, Pferdestärke and PS.

In addition, there are also two electrical horsepower hp(E) units, the electrical horsepower US and the electrical horsepower Europe.

Boiler hp(S), air and hydraulic horsepower complete the units and definitions of hp currently in use as unit of measurement of power; taxable horsepower are out of scope as they depend on jurisdiction and are subject to change. On this page you can find the conversion formulas, a converter, and useful information.



This Horsepower ⇄ Kilowatts Converter is Really Cool! Click To Tweet

Enter your amount of hp, then proceed with the default or select your particular unit from the drop down menu.

After that, hit the Convert button. To start over, press the Reset button.

Here you can find all about kW to hp, including a converter.


To convert horsepower to kilowatt choose the appropriate formula below, taking into account what hp(X) stands for, I = mechanical = imperial, M = metric, E = electric, and S for steam (boiler):

  • [kW] = [hp(I)] × 0.74569987158227022
  • [kW] = [hp(M)] × 0.73549875
  • [kW] = [hp(E) US] × 0.746
  • [kW] = [hp(E) Europe] × 0.735
  • [kW] = [hp(S)] × 9.810657

(To convert hydraulic hp or air hp, use the same formula as for mechanical horsepower.)

If you are from the US and want to know the power of your car motor, then use mechanical hp, hp(I).

Visitors from Europe should rather choose metric hp, hp(M), for the same purpose.

If you’re not sure which of the bolded units to select, then choose either, because the difference between mechanical horsepower and metric horsepower is small, approximately 1.5%.

You can use the same approach for electrical hp Europe / US to kW: The difference is percentage is relatively small, so either conversion serve can serve as approximation.

Instead of applying the formulas, conduct your transformation using our converter above.

Our tool defaults to mechanical hp as used in car specifications in the United States for example.

In the next part of this page, we show you a couple of sample conversions including bhp to kW, and then discuss the frequently asked questions in the context of hp kW.

Horsepower to Kilowatts

Here we demonstrate how to convert the power means of examples, using the formulas:

For a new car sold in the US, labelled 240 hp, we multiply the power in horsepower by 0.74569987158227022 and obtain as equivalence 178.97 kilowatts.

In case of a truck advertised with 400 hp in Europe, for example in Germany, we multiply the hp by 0.73549875 and get the equivalence of 294.1995 kW.

In case of an electric engine with a power of 50 hp, multiply the value by 0.746 for US motors or by 0.735 for European machines.

The results are 37.3 kW and 36.75 kW, respectively.

Supposed a boiler’s capacity to produce steam is 10 bhp (hp(s), then you have to multiply the value in boiler hp by 9.810657. The result is 98.11 kilowatts.

Except for bhp to kW you can memorize this rule of thumb: The power in hp is approximately 3/4 the power in kW.

A kW is 103 W = 1000 watts.

The letter k denotes the SI prefix kilo, which stands for thousand.

Therefore, to answer a question like how many watts in a hp multiply the value in kW by 1000.

Next, we are going to explain our custom search form, followed by the summary of our content.


You have reached the concluding section of hp (a term invented by the Scottish engineer James Watt to compare the power of a draft horse with that of a steam engine) in kW.

To change work over time from one unit to another you could also use our search in the sidebar or at the bottom.

The result page contains all relevant posts.

Finally, note that the unit horsepower, while still heavily used in daily life, is a legacy unit which, in many countries, is gradually being phased out and replaced by kilowatts.

Frequent transformations on our site include, among many others:

To sum hp in kW up, we use this image:

For comments, questions and anything else you might have, use the designated form at the bottom of this page, or get in touch by email using a meaningful subject line.

If our article has been helpful to, then do as the a favor and hit the sharing buttons, and don’t forget to bookmark our site.

Thanks for visiting hptokw.com.

Further Information:

– Article written by Mark