hp to kW Converter

How to convert HP to kW?

To convert mechanical horsepower to kilowatts, multiply by 0.7457. The mechanical hp is defined as exactly 550 ft·lbf/s = 745.6999 W, traceable to James Watt's 1782 definition. For metric horsepower (PS), use 0.73549875 instead. The kW is the SI-coherent unit of power.

P_(kW) = P_(hp) × 0.7457

Example

Convert 100 hp to kW:

P_(kW) = 1 hp × 0.7457 = 0.7457 kW

How many kW in 1 hp?

Approximately 0.7457 kW, where 'hp' means mechanical horsepower (exactly 550 ft·lbf/s = 745.6999 W). For metric horsepower (PS), the factor is 0.73549875 kW. For electrical horsepower (NEMA motors), it is exactly 0.746 kW.

How many hp in 1 kW?

Approximately 1.341 hp (mechanical), or 1.3596 PS (metric), or 1.3405 electrical hp.

1 kW ≈ 1.341 hp

What is horsepower and who invented it?

James Watt coined the unit around 1782 to market his steam engine. He observed mine ponies lifting coal and approximated the average rate at 33,000 foot-pounds per minute. Modern mechanical horsepower (the US definition) preserves that figure: 1 hp = 550 ft·lbf/s = 745.6999 W exactly.

1 hp = 0.7457 kW

What are the different types of horsepower?

Mechanical hp (745.7 W, used in US/UK auto industry); metric hp or PS (735.5 W, used in continental Europe); electrical hp (746 W exact, used by NEMA for motor nameplates); boiler hp (9,809.5 W, used for steam boilers). The differences are small but important for specifications.

Why is kW preferred internationally?

Because the kilowatt is the SI-coherent unit of power, the only unit accepted by international standards (ISO, IEC, EU type approval). Horsepower is a legacy unit retained for marketing reasons in the US automotive market. Every datasheet outside the US lists kW first.

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