How Much Horsepower Does a Horse Have?

There is a common misconception that has been tried to clear several times but it still manages to exist, that the power of a horse is equal to the horsepower. This misconception has been living with us since the time humans moved from horses/camels to cars, buses, and other means of transportation. And like many of us, you are here to get the quick answer. 

How much horsepower does a horse have? Since we have been using horsepower (power measuring unit) to define the efficiency of an object. This is the reason why we use the term “horsepower” to determine the efficiency of a horse to perform certain tasks.

Before the engines, cars, machines, and other such equipment took the world by storm most of the work was being done by the horses. They were taking things, working in the factories thus helping humans in many ways. As the horses were replaced by the machines, we started questioning the efficiency of horses.

How much horsepower does a horse have?

The maximum output of a horse is 14.9 or 15 horsepower. A horse can lift 330 pounds of weight 100 feet per minute, 33 pounds of weight 1000 feet per minute, or 1000 pounds of weight 33 feet in one minute.

The purpose of measuring the capacity of a horse in a horsepower unit.

A lot of things have evolved in the 20th century but the horsepower unit is still going strong since the 18th century. Horsepower being a consistent unit of measure defines the forcefulness of the object (under discussion) to perform a certain task. Horsepower tells 

  • About the total running capacity of an object.
  • How much weight it can lift or carry.

In simpler words, the purpose of horsepower is to define the capability of an object understandably.

What is the horsepower of workhorses?

Workhorses are considered the strongest ones among the other breeds. The horsepower of the horses mentioned here is calculated keeping workhorses performance in the mind. So, the maximum output of the workhorses is 15 hp.

For better understanding, let’s compare the horsepower of a horse with a human.

Humans are far behind the horses when we talk about performing tasks that need more strength. The horsepower of a healthy physically active human is 5 hp and the horsepower of a horse is almost 15 hp. So, it can be said that horses can perform better than humans.

Even if the horsepower of a horse is 3 times better than humans, still humans have more endurance:

Horses are sprinters, they go shorter but faster and they carry more but for a short period. Humans are proven to have more endurance, ability to go a long way, than horses, and even cheetahs.

Why do we measure the output of horses in the “horsepower” unit?

This generally accepted formula is understandable to all and it is used to define the output of all working devices so horses are no exception.

We have been defining the output of the horses in terms of horsepower since this unit came into existence. There were no formulas or anything that could define the efficiency of an object back in the 18th century. “Horsepower” was made to compare the work being done by horses with the modern steam engine. And the simplicity of this power measuring unit got so appreciation that with all the electric and mechanical devices we started measuring the output of horses in it.

And there are the  

Factors that affect the horsepower of a horse

Horses may have more horsepower than humans and few other animals that are used for such purposes. But some factors affect the horsepower of a horse. 

  • Weather
  • Health
  • Breed
  • Sex
  • Age


Horses aren’t made for hot weather as their big wide body can not deal with heat. They are more comfortable performing daunting tasks when the temperature is somewhere between 18 to 59 F. When the weather is unfavorable for them they may not be able to perform equal to the 15 horsepower at a time.


Health greatly affects the performance of all mammals on earth. Only a physically fit, healthy horse can have the strength to work at such a pace.


There are certain breeds of horses that are a bit slower and weaker than their fellows. They may not be able to achieve this horsepower goal. Racehorses or these horses that are trained to work under tough conditions are an exception. Such as expecting a 15 hp from a pet horse is a cliche.


As per the law of nature, male horses are bigger and stronger so their tendency to perform something is much higher than the female horses. 


Younger horses that are considered under aged may not be able to work with the same hp as the horses that have reached maturity. Generally, horses start performing better when they reach 2 years of age and at the age of 4.45 years, they are at their peak performance.

horse power

List of horse breeds that are proven to provide 15 horsepower output

Draft horse breeds are commonly known as “workhorses” and they are proven to provide maximum output (15 hp) even under intense conditions. For their remarkable strength and patience, they are still performing the task of machines and labor even in the developed countries of the world.

American cream draft, Belgian, Ardennes, Breton, Boulonnais, Comtois, Clydesdale, Dutch draft, Dole, Fjord, Finnhorse, Freiberger, Haflinger, Friesian, Italian heavy draft, Irish draft, Latvian, Jutland, Noriker, Murakoz, North Swedish horse, Percheron, Polish draft, Pinto draft, shire, Rhenish-German cold blood, Russian heavy draft, Schleswig Holstein, South German cold blood, Soviet heavy draft, spotted heavy draft, Vladimir heavy draft, Suffolk horse are still being used as an alternative to modern machines. 

To make this article less complicated for the readers that do not know the concept of horsepower we have to get a quick look at the concept of the term “horsepower”.

The concept, origin, and the definition of power measuring unit, horsepower:

There are many other ways of measuring the power output of an object but the horsepower is most common of them all. The reason could either be the popularity or the simplicity of the power output measuring unit called horsepower.

What is horsepower?

In simpler words,

A horsepower is a unit that is used to measure the power of motors and engines. One horsepower unit is equal to the power needed to pull a weight of 550 pounds a distance of one foot in one second or to raise 33,000 pounds a distance of one foot in one minute.

“Horsepower” unit was invented in the 18th century when the farmers compared the efficiency of this alien machine with the horse as they were the only source of help at that time. The concept of this power unit is based on the assumption of how much work a healthy horse can perform in a minute.

The history of the unit ” horsepower”.

Before the invention of the car and machines, most of the work on roads and factories was being done by either humans or horses. So, the founder of the steam engine, James Watt, needed a way to describe the power of the engine that is ready to get into the market. He used horses to make people understand the power of the revolutionized engine as at that time horses were the only source of help.

The engine was powerful enough to carry the work of several horses at a time so he created an easy-to-understand unit that can tell how many horses are getting a retirement. Watt knew that farmers would compare the engine with the power of horses. To put their confused mind to rest he developed a unit that could easily answer their questions.

After an experiment, he learned that a horse can carry 33,000 pounds in one minute. And the comparison between the engine and the horses led to the foundation of unit “horsepower”.

Horsepower means the power of one horse- how did the misconception arise?

What do you get from the word “Horsepower” if you have never come across this word anytime in your life? You will probably say “the power of a horse”. When the ” horsepower” was officially recognized as a unit to measure the power no one knew the history behind its origin we just started assuming that the power of one horse is equal to the unit “horsepower”. 

Types of horsepower unit

Like definitions, horsepower has different types as well. The two most common ones are:

  • Mechanical or Imperial horsepower
  • Metric horsepower

Mechanical or Imperial horsepower

A mechanical horsepower is a unit of power that requires the object to lift 550 pounds/250 kg by one foot in one minute and it is represented by the symbol hp.

Metric horsepower

Metric horsepower is not different from mechanical or imperial horsepower. It got separated because it is calculated and presented differently. The metric horsepower is therefore about 735.5 watts when imperial horsepower is 745.7 watts.

The Horsepower unit has different definitions

While searching for an accurate answer, you may have come across several definitions and this might have thrown you into confusion as to which one is true? All of them are true. Here is why:

The definition of horsepower depends on regional variations and the type of machinery or object, requiring you to measure its power.

In the case of Imperial horsepower (also known as Mechanical horsepower) one horsepower unit is equal to 745.7 watts of power.

For metric horsepower one unit is equal to 735.5 watts and for electric motors, it equals to 746 watts.

For the steam boiler, the view of the horsepower unit is not even close to the above-mentioned cases as it’s one unit is equal to 9,810 watts.

This is the reason why we get confused with the definitions of the horsepower unit.

what is the horsepower of a horse

Horsepower formula

As the horsepower is just a rate at which the work is being done at a time so the common horsepower formulas are:

Horsepower = Work/Time

(This formula is not usually used to calculate horsepower as it does not give as accurate information as you need but explains the theory of this power measuring unit very well)

Horsepower = torque*RPM/5252

(In this formula, RPM is the speed of the engine, T is torque, and 5252 represents the radians per second.)

Frequently Asked Questions

What is hp?

Hp is a short form of a power measuring unit called horsepower. 

What is the horsepower of a horse?

The maximum output of a horse is either 14.9 or 15 hp. And this calculation is based on the horsepower of all breeds of horses, especially workhorses. 

What does horsepower mean?

As per general assumption, horsepower means “the power of a horse” but in reality, it is just a name Watt used to refer the power measuring unit with.

Is one horsepower equal to the power of one horse?

No, this statement (one horsepower is equal to the power of one horse) is misleading as a healthy horse can give output up to fifteen horsepower at a time. So assuming one unit of horsepower equal to the power of a horse is all wrong.

Is it true or that horsepower means the power of a horse?

No, the horsepower is an output measuring unit it has nothing to with the power of a horse. It is rather used to measure the output a horse can give while performing a dreadful task.

Final Words

the horsepower of a horse is 15 hp. This calculation is based on taking into account the horses that were working in the factories back in the 18th century.  Horsepower is a widely known output measuring unit that is not only used to measure the output of machines and vehicles but horses also. The meaning of horsepower being the power of the horse is just a misconception. Horsepower is not equal to the power of horses.

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Hi, I am Waqar and active in the horse world since 2012. I have MSc (Hons) in Agriculture from the University of Agriculture Faisalabad. I love to solve equine health care issues and note down in the form of research papers. I have written hundreds of equine health care, accessories, names, and history-related blogs. My equine related work is watering a lot of horse-related magazines and blogs.

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