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Watts, kilowatts and mechanical horsepower.
Choose a conversion below. Every tool includes an instant result, an example and a short explanation.
Power is the rate at which energy is transferred. A watt means one joule per second; a kilowatt means one thousand watts. Vehicle, motor and equipment specifications sometimes quote mechanical horsepower, a legacy unit that can be compared with SI power once its definition is clear.
The horsepower unit here is mechanical horsepower based on 550 foot-pounds force per second, equivalent to about 745.6998716 W. Metric horsepower and electrical horsepower use different factors. A nameplate rating may also refer to input, shaft output, peak or continuous power. Converting the unit cannot reconcile those different measurement conditions.
Power is the rate at which energy is transferred or used. A kilowatt is a power unit; a kilowatt-hour is energy equal to one kilowatt maintained for an hour. Converting watts to horsepower does not tell you energy consumption until you also know the operating time and, where relevant, efficiency.
Several horsepower definitions exist, including mechanical and metric horsepower. A bare “hp” on a product sheet may need clarification before comparison. Use the convention named by the source and check whether an engine rating, motor output or electrical input is being quoted; converting units does not make those different measurements equivalent.