Horsepower to Foot-pounds per Second Converter

To convert a measurement in horsepower to foot-pounds per second, multiply the value by 550. The conversion factor comes from the relationship between both units and the watt.

For example, to convert 5 hp to foot-pounds per second: 5 × 550 = 2,750 ft·lb/s.

Mechanical horsepower (hp) is a unit of power equal to about 745.7 watts, originally defined to compare engine output to the work of draft horses. James Watt coined horsepower in the 1780s to market his steam engines against the horses they replaced. Mechanical horsepower remains the dominant unit for engine power in the United States.

Common uses of horsepower include: Car and motorcycle engine ratings (US); Lawn mowers and power tools; Marine and outboard motors; Comparing engine performance.

A foot-pound per second is an imperial unit of power equal to about 1.356 watts, representing one foot-pound of work performed each second. Rooted in imperial mechanics, the foot-pound per second is the basis from which horsepower was defined — 550 ft·lb/s equals one mechanical horsepower.

Common uses of foot-pounds per second include: Mechanical engineering in imperial units; Deriving horsepower from work rate; Physics work-and-power problems; Legacy machinery specifications.

Here are some common values converted:

1 hp = 550 ft·lb/s 5 hp = 2,750 ft·lb/s 10 hp = 5,500 ft·lb/s 50 hp = 27,500 ft·lb/s 100 hp = 55,000 ft·lb/s