There is no direct conversion for determining the amount of amps in 1 horsepower. In order to convert between the two, it is necessary to know the voltage associated with the amps.
Horsepower and amperage do not measure the same items. Horsepower is used to measure the rate of work, but amperage is a unit used to measure electric current.
One unit of horsepower is equal to 745.7 watts. The watt is the product of the amperage and the voltage. If the voltage associated with the amps is known, the equation to determine the number of amps in one horsepower is 745.7 ÷ voltage = amps.