Horsepower to Watts Converter
Convert horsepower (HP) to watts instantly. Perfect for electrical power, engine ratings, and mechanical calculations.
Formula
\[ \text{Watts} = \text{HP} \times 745.7 \]
Where 1 horsepower (mechanical) equals approximately 745.7 watts.
How It Works
Horsepower is a unit of power originally defined by James Watt to compare steam engine output to the power of draft horses. The mechanical horsepower (also called imperial horsepower) equals 745.7 watts, while the metric horsepower equals 735.5 watts. This calculator uses mechanical horsepower.
Example Calculation
To convert 5 horsepower to watts:
- Multiply 5 HP by the conversion factor 745.7
- 5 × 745.7 = 3728.5 W
- Result: 5 HP = 3728.5 W
Common Use Cases
- Automotive: Engine power ratings and performance comparisons
- Electric Motors: Converting motor specifications between units
- HVAC Systems: Air conditioner and heat pump ratings
- Power Tools: Comparing tool power specifications
- Industrial Equipment: Machinery power requirements
Frequently Asked Questions
What is horsepower?
Horsepower is a unit of power measuring the rate of work. One mechanical horsepower equals 33,000 foot-pounds per minute, or 745.7 watts in SI units.
How many watts are in 1 horsepower?
1 mechanical horsepower (HP) equals 745.7 watts. This is the standard used in the United States and most English-speaking countries for engine ratings.
What's the difference between mechanical and metric horsepower?
Mechanical horsepower (745.7 W) is used in the US and UK, while metric horsepower or PS (735.5 W) is used in Europe. The difference is about 1.4%.
Why do some appliances use watts and others use horsepower?
Electric appliances typically use watts (SI unit), while mechanical engines traditionally use horsepower. Both measure power but in different contexts - electrical vs. mechanical.
Data Source and Methodology
The conversion factor is based on the standard definition: 1 HP = 745.699872 watts, commonly rounded to 745.7 watts for practical calculations.