# Watt vs. Horsepower: What's the Difference?

Edited by Sumera Saeed || By Sawaira Riaz || Updated on October 2, 2023

A watt is a unit of power in the International System of Units (SI), and one horsepower is equivalent to 746 watts, measuring the rate at which work is done or energy is transferred.

## Key Differences

A watt (W) is the basic unit of power in the SI system, derived from the meter-kilogram-second (MKS) system of units. It quantifies the rate of energy transfer or conversion, with one watt equivalent to one joule per second. On the other hand, horsepower (hp) is a unit of power that originated from comparing machine power to that of horses, commonly used to describe the power output of engines or motors.

Sawaira Riaz

Oct 02, 2023

Watts are used universally in the measurement of electrical power, among other applications. The watt's versatility allows for its use in describing power in many contexts, including electrical, mechanical, and thermal. In contrast, horsepower is traditionally used in the automotive and machinery industries to describe the power capabilities of engines and is still prevalent due to its early adoption in these sectors.

Sawaira Riaz

Oct 02, 2023

The watt can be used to express power in any form of energy per unit time, making it a versatile and widely accepted measure for power. In comparison, a horsepower specifically represents a rate of doing work equivalent to 550 foot-pounds per second or 745.7 watts, and it is not as versatile as the watt for different applications.

Sawaira Riaz

Oct 02, 2023

To give perspective, one watt is the power produced by a current of one ampere across the potential difference of one volt. Horsepower, however, with its specific conversion factor, serves as a high-magnitude unit suitable for expressing the high power levels involved in engine work and other similar contexts.

Sawaira Riaz

Oct 02, 2023

While the watt's acceptance and application are universal and wide-ranging across various science and engineering fields, the use of horsepower is more specialized and traditional, mainly reserved for vehicles, machinery, and some aspects of aerodynamics. Its continued use is largely attributed to convention and consumer familiarity, especially in the automotive industry.

Sara Rehman

Oct 02, 2023

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## Comparison Chart

### Application

Universal, used in various fields

Primarily in automotive and machinery

Sawaira Riaz

Oct 02, 2023

### Measurement

Measures power in any form of energy per unit time

Measures work done over time, specifically suited for engines

Aimie Carlson

Oct 02, 2023

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## Watt and Horsepower Definitions

#### Watt

Used to quantify power in electrical terms primarily.

The device requires a minimum of 100 watts to operate efficiently.

Janet White

Oct 02, 2023

#### Horsepower

A unit of power equating to 745.7 watts.

This car engine has an output of 300 horsepower.

Sawaira Riaz

Oct 02, 2023

#### Watt

Measures the rate of energy conversion or transfer.

This appliance has a maximum output of 1500 watts.

Janet White

Oct 02, 2023

#### Horsepower

Common in the automotive and machinery industries.

Consumers often consider horsepower when purchasing new vehicles.

Harlon Moss

Oct 02, 2023

#### Watt

Equivalent to one joule per second.

The gadget operates at a mere two watts.

Sawaira Riaz

Oct 02, 2023

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#### Horsepower

Traditionally used to express the power output of engines.

The lawnmower operates at 5.5 horsepower.

Sawaira Riaz

Oct 02, 2023

#### Watt

A unit of power in the International System of Units (SI).

A 60-watt bulb consumes 60 joules of energy per second.

Aimie Carlson

Oct 02, 2023

#### Horsepower

Developed to compare the power of machines to that of horses.

Early steam engines were often measured in horsepower to illustrate their capabilities.

Harlon Moss

Oct 02, 2023

#### Watt

Can represent power in terms of mechanical, thermal, or electrical energy.

The heater has a power rating of 2000 watts.

Sara Rehman

Oct 02, 2023

#### Horsepower

Represents the rate of doing work.

The motor's capacity is 150 horsepower, indicating its robust performance.

Janet White

Oct 02, 2023

#### Watt

An SI-derived unit of power equal to one joule per second. See Table at measurement.

Sawaira Riaz

Oct 16, 2022

#### Horsepower

Abbr. hp A unit of power in the US Customary System, equal to 745.7 watts or 33,000 foot-pounds per minute.

Sawaira Riaz

Oct 16, 2022

#### Watt

In the International System of Units, the derived unit of power; the power of a system in which one joule of energy is transferred per second. Symbol: W

Sawaira Riaz

Oct 16, 2022

#### Watt

A unit of power or activity equal to 107 C.G.S. units of power, or to work done at the rate of one joule a second. An English horse power is approximately equal to 746 watts.

Sawaira Riaz

Oct 16, 2022

#### Horsepower

(Informal) Effective strength

Political horsepower.

Computer horsepower.

Sawaira Riaz

Oct 16, 2022

#### Watt

A unit of power equal to 1 joule per second; the power dissipated by a current of 1 ampere flowing across a resistance of 1 ohm

Sawaira Riaz

Oct 16, 2022

#### Watt

Scottish engineer and inventor whose improvements in the steam engine led to its wide use in industry (1736-1819)

Sawaira Riaz

Oct 16, 2022

#### Horsepower

A nonmetric unit of power (symbol hp) with various definitions, for different applications. The most common of them is probably the mechanical horsepower, approximately equal to 745.7 watts.

Sawaira Riaz

Oct 16, 2022

#### Horsepower

A metric unit (symbol often PS from the German abbreviation), approximately equal to 735.5 watts.

Sawaira Riaz

Oct 16, 2022

## FAQs

#### How does Watt relate to energy?

Watt measures the rate of energy conversion or transfer.

Sawaira Riaz

Oct 02, 2023

#### Can a watt measure mechanical power?

Yes, it can represent power in mechanical, electrical, or thermal terms.

Janet White

Oct 02, 2023

#### What is a Watt?

It is the SI unit of power equivalent to one joule per second.

Sawaira Riaz

Oct 02, 2023

#### What does Horsepower measure?

It measures the rate at which work is done, commonly used for engine power.

Sawaira Riaz

Oct 02, 2023

#### How many watts are in one Horsepower?

One horsepower is equivalent to 746 watts.

Harlon Moss

Oct 02, 2023

#### Is Horsepower only used for vehicles?

It’s primarily used for vehicles but also for other machinery.

Sawaira Riaz

Oct 02, 2023

#### Can Watt measure electrical power?

Yes, it is commonly used to measure electrical power.

Sawaira Riaz

Oct 02, 2023

#### How is Horsepower calculated?

It’s traditionally calculated as 550 foot-pounds of work per second.

Sawaira Riaz

Oct 02, 2023

#### Where is Horsepower most commonly used?

It’s most commonly used in the automotive and machinery industries.

Sara Rehman

Oct 02, 2023

#### Why is Horsepower still in use?

It remains in use due to tradition and consumer familiarity, especially in the automotive sector.

Sawaira Riaz

Oct 02, 2023

#### Why is Horsepower called so?

It was developed to compare the power of steam engines to horses.

Aimie Carlson

Oct 02, 2023

#### Is Watt used universally?

Yes, it is a universal unit used across various fields for measuring power.

Sara Rehman

Oct 02, 2023

#### What is the origin of Horsepower?

It was coined by James Watt in the 18th century to compare steam engine power to horse power.

Harlon Moss

Oct 02, 2023

#### Can Horsepower be converted to other power units?

Yes, it can be converted to other units like watts or BTUs, using specific conversion factors.

Harlon Moss

Oct 02, 2023

#### Is one unit superior to the other?

No, they are used in different contexts; watt is more versatile, horsepower is more specific.

Janet White

Oct 02, 2023

#### Is the wattage of an appliance the energy it uses?

It represents the rate of energy use, not the total energy consumed.

Sara Rehman

Oct 02, 2023

#### Can Watt measure power of any form of energy?

Yes, it can measure the power of any form of energy conversion or transfer.

Sara Rehman

Oct 02, 2023

About Author

Written by

Sawaira RiazSawaira is a dedicated content editor at difference.wiki, where she meticulously refines articles to ensure clarity and accuracy. With a keen eye for detail, she upholds the site's commitment to delivering insightful and precise content.

Edited by

Sumera SaeedSumera is an experienced content writer and editor with a niche in comparative analysis. At Diffeence Wiki, she crafts clear and unbiased comparisons to guide readers in making informed decisions. With a dedication to thorough research and quality, Sumera's work stands out in the digital realm. Off the clock, she enjoys reading and exploring diverse cultures.