How to convert horsepower to watts
To convert a measurement in horsepower to watts, multiply the value by 745.699872. The conversion factor comes from the relationship between both units and the watt.
For example, to convert 5 hp to watts: 5 × 745.699872 = 3,728.4994 W.
What is a horsepower?
Mechanical horsepower (hp) is a unit of power equal to about 745.7 watts, originally defined to compare engine output to the work of draft horses. James Watt coined horsepower in the 1780s to market his steam engines against the horses they replaced. Mechanical horsepower remains the dominant unit for engine power in the United States.
Common uses of horsepower include: Car and motorcycle engine ratings (US); Lawn mowers and power tools; Marine and outboard motors; Comparing engine performance.
What is a watt?
A watt is the SI derived unit of power, equal to one joule of energy per second (1 J/s). Named after Scottish engineer James Watt, whose steam-engine improvements powered the Industrial Revolution. The watt became the SI unit of power in 1960 and now measures everything from light bulbs to power plants.
Common uses of watts include: Light bulb and appliance ratings; Electronic device power consumption; Audio amplifier output; Scientific and electrical calculations.
Horsepower to watts worked examples
Here are some common values converted:
1 hp = 745.699872 W 5 hp = 3,728.4994 W 10 hp = 7,456.9987 W 50 hp = 37,284.9936 W 100 hp = 74,569.9872 W
Frequently asked questions
How many watts are in one horsepower?
One horsepower (hp) equals 745.699872 watts (W). Multiply any value in horsepower by 745.699872 to convert to watts.
How do I convert horsepower to watts?
Multiply the value in horsepower by 745.699872. For example, 5 hp × 745.699872 = 3,728.4994 W.
How do I convert watts to horsepower?
Multiply the value in watts by 0.00134102209, or divide by 745.699872. Use the swap button on the converter above to reverse the direction.
Is the horsepower to watt conversion exact?
Mechanical horsepower is defined as exactly 745.7 W and metric horsepower as 735.49875 W. SI conversions are exact.
What is the formula for horsepower to watts?
The formula is: W = hp × 745.699872. This comes from the definition of both units relative to the watt.