1.341
HP
1
kW
1.341
HP
1
kW
The Watts to Horsepower Converter converts power from watts (W) to mechanical horsepower (HP) using the standard conversion factor 1 HP = 745.7 watts. This is one of the most commonly needed power conversions in automotive engineering, motor specification, and industrial equipment rating.
The watt is the SI unit of power, while horsepower remains the dominant unit for rating engines, motors, and mechanical equipment in the United States and United Kingdom. James Watt himself introduced horsepower in the 1780s to help sell his improved steam engines — he defined it as the power of a horse turning a mill wheel, which he estimated at 33,000 foot-pounds per minute (745.7 watts).
Converting watts to horsepower is essential for comparing electric motors with combustion engines, interpreting equipment specifications, and communicating power ratings to audiences accustomed to different unit systems. For example, a Tesla Model 3 motor produces about 211 kW, which is equivalent to 283 HP — a figure more intuitive to car enthusiasts in the US.
Note that several variants of horsepower exist: mechanical (brake) HP = 745.6999 W (used in this converter), electrical HP = 746 W, metric HP (PS/CV) = 735.499 W, and boiler HP = 9809.5 W. The differences between mechanical and electrical HP are negligible (0.04%), but metric HP differs by about 1.4%. Always verify which definition is being used.
Our converter also provides kilowatt output, as kW is increasingly used for motor ratings internationally. The EU has mandated kW for vehicle power ratings since 2010, though HP/PS values are still commonly quoted alongside.
The formula: HP = watts ÷ 745.7. For kilowatts: kW = watts ÷ 1000. The mechanical horsepower is defined as exactly 33,000 ft·lbf/min, which equals 745.69987 W.
Engine reference points: a typical car engine produces 100–300 HP (75–224 kW), a lawn mower 3–25 HP (2–19 kW), an industrial motor 1–500 HP (0.75–373 kW), and a ship engine up to 100,000 HP (74,570 kW).
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Results
150 kW ≈ 201 HP electric motor
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Results
746 W ≈ 1 HP (electrical HP definition)
1000 watts = 1.341 HP (mechanical). This is roughly the power of a small portable generator.
1 mechanical HP = 745.69987 W, commonly rounded to 745.7 W. 1 electrical HP = 746 W exactly.
Mechanical (brake) HP = 745.7 W, electrical HP = 746 W, metric HP (PS/CV) = 735.5 W, boiler HP = 9809.5 W. This converter uses mechanical HP.
Multiply kW by 1.341. For example, 100 kW = 134.1 HP. Or divide kW by 0.7457.
Watt needed a relatable unit to market his steam engines. He observed horses turning a mill and estimated their output at 33,000 ft·lbf/min, creating a benchmark customers could understand.
Yes, HP remains the standard for engine and motor ratings in the US, UK, and automotive industry worldwide. The EU requires kW but also allows HP/PS in parentheses.
A healthy human can sustain about 75 W (0.1 HP) of mechanical output. Peak power during sprinting can reach 400–2000 W (0.5–2.7 HP) for brief periods.
Brake horsepower (BHP) is measured at the engine output shaft using a dynamometer. Shaft HP is the power delivered to the driven equipment, after transmission losses.
Electric motor HP ratings indicate mechanical output power, not electrical input. A 10 HP motor outputs 7457 W mechanically but draws more from the supply due to motor efficiency (typically 85-95%).
Divide watts by 735.499. For example, 1000 W = 1.360 PS. Metric HP is used in Germany (PS), France (CV), and Japan.
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