HP to ft-lb/min Calculator
Convert horsepower to foot-pounds per minute (the original definition of HP).
This converter shows horsepower in foot-pounds per minute — the exact unit James Watt used when he defined one horsepower as 33,000 foot-pounds of work per minute.
HP to ft-lb/min Formula
This is where horsepower comes from. Watt measured that a horse could do roughly 33,000 foot-pounds of work each minute, and that figure became the definition of one horsepower — which is also why the constant 5252 (33,000 ÷ 2π) appears in the torque formula.
How to Use This Calculator
- Enter horsepower.
- Read ft-lb/min, with ft-lb/sec also shown.
Worked Example
Frequently Asked Questions
One horsepower equals 33,000 foot-pounds per minute, or 550 foot-pounds per second. This is the original definition by James Watt.
James Watt estimated a strong draft horse could do about 33,000 foot-pounds of work per minute, and used that as one horsepower to rate his steam engines.
The 5252 in the torque formula equals 33,000 ÷ 2π. Both trace back to the same 33,000 ft-lb/min definition of horsepower.
Multiply horsepower by 550, since 33,000 per minute divided by 60 seconds equals 550 per second.
A foot-pound is a unit of work (or energy) — one pound of force acting through one foot. Foot-pounds per minute is therefore a unit of power.