How to Convert Car Power and Horsepower?
3 Answers
Power is a physical quantity, horsepower is a unit, and there is no direct conversion between them. The unit of power is watts, and the conversion between watts and horsepower is: 1 metric horsepower = 75 kilogram-force·meter/second = 735 watts. Here is more information about car power: 1. Meaning of power: Power refers to the amount of work done by an object per unit time, that is, power is a physical quantity that describes how fast work is done. With a fixed amount of work, the shorter the time, the greater the power value. 2. Meaning of horsepower: Horsepower is a commonly used unit of power in engineering. It generally refers to metric horsepower rather than imperial horsepower. It is conventionally agreed that 1 metric horsepower is equal to the work done to lift a 75-kilogram object by 1 meter in 1 second. Metric horsepower is entirely man-made, taking a value very close to imperial horsepower. It is defined that 1 metric horsepower is the work done to complete 75 kilogram-force·meters in 1 second. That is: 1 metric horsepower = 75 kilogram-force·meter/second = 735 watts.
Recently, while studying car performance, I figured out the conversion between power and horsepower. It turns out that horsepower is one unit, while power is a metric unit. The basic formula is that 1 horsepower is approximately equal to 0.735 kilowatts, or conversely, 1 kilowatt is about 1.36 horsepower. Remembering this number is simple. For example, my car's engine outputs 150 horsepower, which converts to power by multiplying 150 by 0.735, giving approximately 110 kilowatts. This makes it very convenient when comparing the performance of different car models. The kilowatt unit for power is more precise and commonly used in technical specifications internationally, while horsepower is easier for people to understand in terms of performance feel, especially in racing or daily driving. Europe and America prefer using horsepower, while China and many other places commonly use kilowatts. Knowing this conversion has cleared up my confusion. When looking at car advertisements or manuals, I can quickly do mental calculations to see if the claimed values are realistic. For instance, if a car claims 200 horsepower but has a low power output, it might be exaggerated. Learning this knowledge doesn’t take much time—just remember the core relationship, and you can easily look it up online. In short, the conversion between power and horsepower is basic car knowledge. With a bit of practice, it becomes second nature, and it helps me make more reliable judgments about actual power performance when choosing a car.
I figured it out through my experience in car repair—converting between power and horsepower is actually a practical skill. Horsepower is the old unit, while kilowatts are the new standard, and the relationship boils down to a simple multiplier: 1 horsepower is roughly 0.735 kilowatts, or conversely, 1 kilowatt equals about 1.36 horsepower. Back when I was young and drove trucks, horsepower was the go-to measurement, but nowadays, more cars list power in kilowatts. Whenever I need to convert, I just use my phone's calculator or do a quick mental calculation. For example, if a car's power is labeled as 80 kW, multiplying by 1.36 gives roughly 108 horsepower—this makes comparing performance straightforward. Different countries prefer different units: the U.S. often uses HP, Europe favors PS, while kilowatts (kW) are the metric standard. Understanding this ensures no mistakes when interpreting data from repair tools or diagnostics. Also, remember that as an engine wears out and loses power, you can still convert the drop in kilowatts to quantify the horsepower loss. On the road, this conversion helps you react faster to performance changes without needing specialized tools—just a simple number to remember is enough for everyday maintenance.
