Thus, the current I in amps is equal to the power P in horsepower times 746, divided by the product of the voltage V, efficiency η, and power factor PF.

You can convert horsepower to amps of input current in a few simple steps, or using this simple formula which uses the output power of the motor, efficiency of the motor, RMS voltage input and power factor. Horsepower is commonly used to state the output power of an electric motor. Electric horsepower (HP) is a measure of electric power equal to 746 watts (W).