The term “horsepower” gets thrown around a lot. You’ve likely heard it in countless car commercials, movies and TV shows. These days, it’s even used in advertisements for chainsaws and lawnmowers. Still, you might have a hard time finding someone who can actually tell you its true meaning. So, what is horsepower and how does it indicate a car’s performance?
Why it’s called “horsepower”
When someone says their car’s engine has X-hundred horsepower, what are they talking about? Does it mean you'd need that many physical horses to bring the car up to the same speed? Not quite. To truly understand the relationship between horses and engines, a short history lesson is in order.
James Watt: the father of horsepower
James Watt was a brilliant 18th-century inventor and engineer whose transformation of the steam engine earned him the title of father of the industrial revolution. In a market literally driven by horses, people had a hard time understanding just how much better Watt’s steam engine was, so he needed to find a common scale between horses and engines in order to measure the benefit his engine provided.
He began by looking at mill horses turning the giant spokes of a mill wheel at a steady rate for hours every day — the true definition of a “workhorse.” After some experimentation and calculation, Watt came up with a measurement for the average amount of work a horse could do in one minute. This new unit, aptly named “horsepower,” was Watt’s new marketing tool. He finally had a way to compare the power of his engine with the power of horses.
How is horsepower measured?
In scientific terms, one unit of horsepower is equivalent to 33,000 foot-pounds of work in one minute (or 550 foot-pounds of work in one second). You could visualize this as a horse moving 33 pounds over a 1,000-foot distance in one minute, or moving 1,000 pounds over 33 feet in one minute.
Horsepower is important because it helps us gauge a car’s potential. In a very general sense, the greater the horsepower a car has, the more potential work it can do — whether that’s going really fast or hauling a lot of weight.
What is the average horsepower of a vehicle?
Most cars on the market today tend to fall within a few different ranges of horsepower (HP) based on the type of vehicle it is. Note that these ranges are estimates, as there isn’t any industry-wide standardization for how much horsepower a vehicle should have.
General consumer cars
Typical consumer cars, like a four-door sedan, may fall around 100 and 200 HP. Some compact cars may come slightly under that figure, while midsized and family cars, like a van or SUV, may be toward the top of this range or beyond.
Performance cars and trucks
Performance sedans and sports cars may boast horsepower figures in excess of 300 HP. Trucks and larger SUVs may also have HP in the 300 to 400 range, as their horsepower may be needed to haul a lot of extra weight.
Supercars are engineered to deliver unparalleled speed and power in a designer package. These cars may pack 500 HP or more under the hood for a truly heart-pumping drive.
A car’s horsepower is given a lot of weight by buyers, and rightly so — it speaks directly to the car’s performance. While some people stick to the logic that more is better, maxing out horsepower may not be right for everyone. It’s important to consider your own needs to determine how much horsepower is best for you.