Liquids can have the power of horses. Hydraulic horsepower refers to the power that a hydraulic system can generate. The horsepower depends on the gallons per minute (gpm) of the flow of fuel and the pressure rate of pounds per square inch (psi). If you know both of these factors, then you can convert psi into hydraulic horsepower. Converting psi into hydraulic horsepower can help you define the efficiency of the system.

Determine the flow of the liquid in gallons per minute (gpm). For example, the given flow of the liquid is 20 gallons per minute.

Multiply that gallons per minute by the amount in psi. For the example, the amount in psi is 400. That multiplied by 20 gpm equals 8,000.

Divide that number by 1,714 to obtain the hydraulic horsepower. For the example, 8,000 divided by 1,714 equals 4.667 hydraulic horsepower.