The kilowatt (kW) equals 1,000 watts and is the standard unit for measuring the power output of engines, electric heaters, and industrial machinery. Electricity bills use kilowatt-hours (kW × hours), making the kilowatt the most familiar power unit for consumers. One kilowatt equals approximately 1.341 horsepower.

Horsepower (hp) is an imperial unit of power equal to approximately 745.7 watts, originally defined by James Watt to compare steam engine output to draft horses. It remains the standard unit for rating car engines, lawnmowers, and boat motors, especially in the United States. One horsepower equals about 0.7457 kilowatts or 1.0139 metric horsepower.