PSI to GPM Calculator

Fluid Dynamics & Hydrostatic Orifice Flow

Pressure (pounds per square inch) and volumetric flow rate (gallons per minute) are governed by Torricelli's Law and the Bernoulli Energy Equation. Fluid cannot flow through a pipe or orifice without a pressure differential $\Delta P$.

Core Hydraulic Flow Equations

• Freeman's Nozzle Orifice Discharge: $Q = 29.83 \times C_d \times d^2 \times \sqrt{P}$

• NFPA Fire Sprinkler Equation: $Q = K \times \sqrt{P} \implies P = \left(\frac{Q}{K}\right)^2$

• Control Valve Sizing: $Q = C_v \times \sqrt{\frac{\Delta P}{\text{SG}}}$

• Torricelli Theoretical Jet Velocity: $v = \sqrt{2 g h} = 12.19 \times \sqrt{P} \text{}$

• Hydraulic Horsepower: $\text{HHP} = \frac{P \times Q}{1,714}$

Standard Orifice Discharge Coefficients ($C_d$)

• Smooth Bore Nozzle / Fire Monitor: $C_d \approx 0.97 - 0.99$

• Standard Short Pipe / Spigot: $C_d \approx 0.80 - 0.82$

• Square Sharp-Edged Orifice: $C_d \approx 0.60 - 0.62$.

How to Use This Calculator

Enter Hydraulic System Model, Differential Water Pressure (PSI), Orifice / Nozzle Diameter (d), Discharge Coefficient (Cd) into the input fields and the calculator will instantly compute Water Flow Rate (GPM), Flow Rate (Metric LPM). All calculations happen in real time — no submission or page reload required. You can adjust any input value and see the result update immediately.

Understanding Your Result

The PSI to GPM result gives you a precise, calculated value based on the inputs you provide. Compare your result against published benchmarks from NIST, BIPM, and ISO 80000 to assess where you stand. A single calculation is a useful starting point, but tracking this metric over time — as inputs change — gives you a much more complete picture.

Practical Application

The PSI to GPM is most useful when you have specific, real-world data to enter. For example: enter your actual Hydraulic System Model to calculate your water flow rate (gpm). The result helps engineers, scientists, students, and international traders make informed decisions about converting between measurement units for science, engineering, and commerce. This calculator is trusted by professionals and individuals alike because it follows the exact formulas validated by NIST, BIPM, and ISO

80000.

Accuracy Notes and Limitations

For legal or trade filings, verify conversions against official government or standards body references. The accuracy of any calculator is limited by the quality of the inputs provided. Double-check your units before entering values — unit errors are the most common source of incorrect results. For critical decisions, cross-reference with at least one additional source or professional consultation.

Frequently Used With

This calculator is often used alongside other conversion tools to build a complete analytical picture. Combining multiple related calculations provides stronger evidence for decisions than relying on any single metric. Browse the Conversion category to find complementary calculators for your specific use case.