Valve Cv Calculator

Calculate the required flow coefficient (Cv) for a liquid valve.

For liquids (turbulent, non-flashing). Select a valve whose rated Cv exceeds the result.

Flow rate Q (US GPM)

Pressure drop ΔP (psi)

Specific gravity (water = 1.0)

Required Cv

8.94

Flow20 GPM

ΔP5 psi

Specific gravity1

Pick a valve with rated Cv ≥ 10.73 (≈20% headroom).

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