Horsepower to watts
Type a value in horsepower to see it in watts straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the horsepower box.
- Read the result in watts as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
W = hp × 745.6998716
Multiply the value in horsepower by 745.6998716 to get watts.
Example
To convert 25 hp to watts: 25 × 745.6998716 = 18,642.5 W.
Conversion table
| Horsepower (hp) | Watts (W) |
|---|---|
| 1 | 745.7 |
| 2 | 1,491.4 |
| 3 | 2,237.1 |
| 5 | 3,728.5 |
| 10 | 7,457 |
| 20 | 14,914 |
| 25 | 18,642.5 |
| 50 | 37,285 |
| 100 | 74,570 |
| 250 | 186,425 |
| 500 | 372,850 |
| 1,000 | 745,700 |
About the units
- Horsepower
- Mechanical (imperial) horsepower is 550 foot-pounds-force per second, exactly 745.69987158227022 watts, the figure used in US car specifications.
- Watt
- The SI unit of power, equal to one joule per second.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many watts are in one horsepower?
1 hp = 745.7 W exactly.
How do I convert horsepower to watts?
Use W = hp × 745.6998716. For example, 25 hp = 18,642.5 W.
How many horsepower are in one watt?
1 W = 0.00134102 hp.
What is the difference between mechanical and metric horsepower?
Mechanical horsepower is about 745.7 watts and is used in the US, while metric horsepower (PS) is 735.5 watts and is used in Europe and Japan. The same engine therefore shows a PS figure about 1.4% higher.
How many kilowatts is one ton of refrigeration?
One ton of refrigeration is 12000 BTU per hour, about 3.517 kW of cooling capacity. That is cooling output, not electricity use; the unit draws less power depending on its efficiency.