Watts to horsepower
Type a value in watts to see it in horsepower 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 watts box.
- Read the result in horsepower as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
hp = W × 0.00134102209
Multiply the value in watts by 0.00134102209 to get horsepower.
Example
To convert 25 W to horsepower: 25 × 0.00134102209 = 0.0335256 hp.
Conversion table
| Watts (W) | Horsepower (hp) |
|---|---|
| 1 | 0.00134102 |
| 2 | 0.00268204 |
| 3 | 0.00402307 |
| 5 | 0.00670511 |
| 10 | 0.0134102 |
| 20 | 0.0268204 |
| 25 | 0.0335256 |
| 50 | 0.0670511 |
| 100 | 0.134102 |
| 250 | 0.335256 |
| 500 | 0.670511 |
| 1,000 | 1.34102 |
About the units
- Watt
- The SI unit of power, equal to one joule per second.
- Horsepower
- Mechanical (imperial) horsepower is 550 foot-pounds-force per second, exactly 745.69987158227022 watts, the figure used in US car specifications.
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 horsepower are in one watt?
1 W = 0.00134102 hp exactly.
How do I convert watts to horsepower?
Use hp = W × 0.00134102209. For example, 25 W = 0.0335256 hp.
How many watts are in one horsepower?
1 hp = 745.7 W.
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.