Conversion

PSI to GPM Calculator

Estimate GPM from PSI for a given orifice or pump curve.

Calculated Output

Flow rate (GPM) 187.84

Formula: GPM ≈ 29.7 × D² × √PSI (sharp orifice)

Step-by-Step Breakdown

1. Values used:

2. Orifice/hole diameter = 1

3. Pressure = 40 psi

5. Flow rate = 187.84GPM

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The math behind it

GPM ≈ 29.7 × diameter² × √PSI (for a sharp-edged orifice discharging to atmosphere).

1 in orifice at 40 psi → ~188 GPM.

Exact?

No — it's a hydraulic estimate; real flow depends on geometry and losses.