To convert a valve’s CV (Flow Coefficient) into GPM (Gallons Per Minute), you need two key pieces of information: the CV value of the valve, and the pressure drop (ΔP) across the valve, measured in PSI (pounds per square inch).

The standard formula for converting CV to GPM under defined flow conditions is:

Where:

• CV = Flow Coefficient of the valve

• ΔP = Pressure drop across the valve (in PSI)

• SG = Specific gravity of the fluid (for water, SG = 1.0)

For most water-based applications, the specific gravity (SG) is taken as 1.0, which simplifies the formula to:

This simplified version is commonly used for water or similar fluids under standard conditions.

To make your calculations faster and more accurate, use our online CV to GPM calculator — just enter your CV and ΔP values, and it will instantly display the GPM flow rate.