Power Unit Converter
Convert between SI power units and horsepower, BTU/hour, and foot-pound/second. Mechanical horsepower and metric horsepower are listed as separate units so a car or motor spec is never converted with the wrong one.
Conversion reference
| From | To | Result |
|---|---|---|
| 1 kW | Horsepower (mechanical) (hp) | 1.3410220896 hp |
| 1 kW | Horsepower (metric, PS) (PS) | 1.3596216173 PS |
| 1 kW | BTU per hour (BTU/h) | 3412.14163313 BTU/h |
| 1 hp | Watt (W) | 745.699871582 W |
| 1 hp | Kilowatt (kW) | 0.745699871582 kW |
| 1 PS | Watt (W) | 735.49875 W |
| 1 PS | Kilowatt (kW) | 0.73549875 kW |
| 1 MW | Kilowatt (kW) | 1000 kW |
| 1 MW | Horsepower (mechanical) (hp) | 1341.0220896 hp |
Values are generated by the converter engine, at Auto precision.
About this converter
Power is the rate at which energy is transferred, measured in watts (one joule per second). This tool expresses both units in watts and takes the ratio.
The two horsepower definitions are close but not equal, so they are separate entries: Horsepower (mechanical) ≈ 745.70 W and Horsepower (metric, PS) ≈ 735.50 W. Pick the one your source uses.
How to use it
- Type the power value in the Value field.
- Choose the unit to convert from — check whether your source means mechanical or metric horsepower.
- Choose the unit for the answer.
- Read the result, Copy it, or Swap to reverse the direction.
The result updates as you type — there is no Calculate button. Use Swap to reverse the two units, and Reset to return to the defaults.
Constants and common values
- 1 W = 1 J/s (base unit)
- 1 hp (mechanical) = 550 ft·lbf/s = 745.6998715823 W
- 1 hp (metric, PS) = 75 kgf·m/s = 735.49875 W
- 1 BTU/h = 0.2930710702 W
- 1 ft·lbf/s = 1.3558179483 W
- 1 kW ≈ 1.34102 hp (mechanical) ≈ 1.35962 hp (metric)
FAQ
What is the difference between mechanical and metric horsepower?
Mechanical (imperial) horsepower is 550 foot-pounds-force per second ≈ 745.6999 W. Metric horsepower (PS, or "cheval") is 75 kgf·m/s ≈ 735.49875 W — about 1.4% smaller. Car specs from different regions use different ones, so this converter keeps them separate.
How many watts is one horsepower?
About 746 W for mechanical horsepower and about 735.5 W for metric horsepower. One kilowatt is roughly 1.341 mechanical hp or 1.360 metric hp.
Which BTU is used for BTU/hour?
The International Table BTU, giving 1 BTU/h = 0.29307107 W. Heating and air-conditioning capacity is usually quoted in BTU/h; 12,000 BTU/h is one "ton" of cooling ≈ 3.517 kW.
Is power the same as energy?
No. Power is the rate of energy transfer (energy per unit time). A 2 kW heater running for 1 hour uses 2 kWh of energy. Use the Engineering converter for energy units.
Don't see the tool you need?
Goeroe Digital builds custom calculators, generators, and business tools on request.
Request a Custom ToolThis is a free tool provided by Goeroe Digital. All results, generated files, and figures are estimates or drafts for general informational use only. Goeroe Digital accepts no responsibility or liability for any output, outcome, loss, or decision arising from the use of these free tools — always review the results yourself before relying on them.