The pressure of water is measured in pounds per square inch (PSI). The flow rate is measured in Gallons per minute (GPM). EasyFreeCalculator's PSI to GPM calculator provides a quick conversion of water pressure to flow rate. It uses examples and equations to demonstrate how to calculate flow rate. It is fast, easy, and useful for irrigation, plumbing setups and water supply.
Direct conversion of GPM from PSI is not possible. As water flow capacity also depends on the real-world factors:
The standard formula for flow rate in gpm is:
Where:
Pressure = 50 PSI
Pipe inside diameter = 1 inch
Step 1: Square the pipe diameter
12= 1
Step 2: Find the square root of PSI
50 = 7.07
Step 3: Multiply values
GPM = 29.84 × D2× PSI
= 29.84 × 1 × 7.07
GPM ≈ 211
The GPM is approximately 211 for a 1-inch pipe at 50 PSI under ideal conditions.
This calculator is commonly used for:
Most people overlook the factors mentioned below, even though they can significantly affect water flow accuracy. Avoid these common mistakes while calculating flow rate.
Yes. Smaller pipes restrict flow as they cause higher friction and turbulence, which will reduce the gallons of water moving through the system.
A discharge coefficient is the efficiency of the water flow from a nozzle, faucet, or fixture. It improves the accuracy of pressure and flow calculations.
Yes. Higher water pressure generally increases flow rate if pipe size and other conditions remain the same.
Fluid properties like density and viscosity play a big role in how turbulence happens or pressure drops in pipes. They also influence the whole flow setup in industrial systems.