# HP Horsepower Watt Calculator

Find the rotating horsepower (HP) using this online Horsepower Calculator based on the torque and speed of the rotating object. Horsepower is a measure of the rate at which work is done and is usually measured in watts. It was originally defined to allow the output of steam engines to be measured and compared with the power output of draft horses. In this online HP Horsepower Watt Calculator, enter the torque and speed to find the HP of rotating object.

### Example:

Calculate rotating HP for torque as 5 lbf·ft and speed as 9 rpm.

#### Solution:

HP Horsepower Watt = 5 x (9 / 5252)

= 0.008568 Watt.