Water Supply Line Size Calculator | Optimal Pipe Sizing

This tool helps you determine the appropriate size for your water supply line.

How to use the Water Supply Line Size Calculator

This calculator helps you determine the necessary pipe diameter for your water supply line based on several parameters:

  • Number of Fixtures: The total number of water fixtures (e.g., faucets, showers) connected.
  • Pipe Length: The total length of the pipe in feet.
  • Flow Rate per Fixture: The flow rate for each fixture in GPM (gallons per minute).
  • Supply Pressure: The water supply pressure in PSI (pounds per square inch).
  • Pipe Material: The material of the pipe (e.g., Copper, PEX, CPVC).
  • Elevation Change: The elevation change in feet (if any) in the pipe’s path.

Once you fill in these values, click “Calculate” to determine the required pipe diameter in inches.


This calculator provides an estimate based on simplified assumptions and may not account for all variables in real-world scenarios. It’s always recommended to consult with a professional plumber or engineer for precise calculations and appropriate material selection.

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