Pipe Flow Rate Calculator
Calculate water flow rate, velocity, and friction loss based on pipe diameter, pressure, length, and material.
Inputs
in
PSI
ft
Results
Flow Rate
1.05 GPM
Velocity0.76 ft/s
Friction Loss40 PSI/100ft
Total Head Loss92.4 ft
Flow Rate (metric)3.98 L/min
How to Use This Calculator
- Enter Pipe Diameter (inches) and Supply Pressure (psi).
- Set Pipe Length (ft) to account for friction losses.
- Select Pipe Material (Copper, PVC/CPVC, Galvanized Steel, or PEX) for the Hazen-Williams coefficient.
- Review Flow Rate (GPM) at the specified pressure and length.
- Use flow rate to size fixtures, irrigation zones, or booster pumps.
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