Converting between horsepower (HP) and watts is important for various applications, from determining the power output of engines to understanding electrical appliances. Whether you're working with automotive engines or calculating the power consumption of an electrical device, knowing how to convert these units can be crucial for making informed decisions.

## What is Horsepower (HP)?

Horsepower (HP) is a unit of power commonly used to describe the output of engines and motors. One horsepower was originally defined as the ability of a horse to do a certain amount of work over time, but today, it is used to measure the power output of all types of machines.

In mechanical terms, 1 horsepower is defined as 745.7 watts. This means that a machine rated at 1 horsepower can do the work of 745.7 watts over the same period.

## What is a Watt (W)?

The watt is the standard unit of power in the International System of Units (SI). Named after Scottish engineer James Watt, this unit is used to quantify the rate of energy transfer. It is a measure of how much work is being done over time, typically associated with electrical devices and power systems.

One watt is defined as one joule of energy transferred per second. In terms of horsepower, 1 watt is approximately equal to 0.001341 horsepower.

## How to Convert Between HP and Watts

Our HP to Watts and Watts to HP calculator allows you to quickly convert between these two units with minimal effort. Depending on the direction of conversion, the formula is simple:

**To convert HP to Watts:**Multiply the HP value by 745.7. For example, a 5 HP engine is equivalent to 5 x 745.7 = 3728.5 Watts.**To convert Watts to HP:**Multiply the Watts value by 0.00134102. For example, an electrical device rated at 1000 Watts is equivalent to 1000 x 0.00134102 = 1.34 HP.

## Common HP to Watts and Watts to HP Conversions

To help you better understand typical conversions, here are some common examples:

Horsepower (HP) | Watts (W) |
---|---|

1 HP | 745.7 W |

5 HP | 3728.5 W |

10 HP | 7457 W |

0.5 HP | 372.85 W |

## When to Use HP vs. Watts

Horsepower is most commonly used when discussing the output of large engines, such as those found in cars, trucks, boats, and other machines. In contrast, watts are more commonly used to describe the power consumption of electrical appliances, from household items like light bulbs to industrial equipment.

If you need to understand the power of an engine or motor, converting between HP and Watts allows you to compare the performance of different machines more easily, regardless of the units used by the manufacturer.