Gallons Per Minute to Cubic Feet Per Second Calculator

Convert between gallons per minute, cubic feet per second, liters per second, and other flow rate units used in plumbing, irrigation, and engineering.

Flow Rate Conversion

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Conversion Formula

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Conversion Results

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See real-time conversions between different flow units

Flow Rate Conversions

Flow rates are measured in different units depending on the industry and application. Plumbers might talk about gallons per minute, while engineers use cubic feet per second. Irrigation specialists work with liters per second. This calculator helps you convert between all these common flow rate units.

Whether you're sizing pipes, selecting pumps, or planning irrigation systems, having the right flow rate in the right units is crucial for accurate calculations and equipment selection.

When Do You Need Flow Rate Conversions?

Different industries and applications use different flow rate units:

  • Plumbing: Gallons per minute (GPM) for fixture sizing and pipe capacity
  • Irrigation: Gallons per minute or liters per second for system design
  • Engineering: Cubic feet per second (CFS) for hydraulic calculations
  • Environmental: Cubic meters per second for river flow measurements
  • Industrial: Various units depending on system requirements

Common Flow Rate Units

Imperial Units

GPM Gallons per Minute Plumbing, irrigation
CFS Cubic Feet per Second Engineering, hydraulics
CFM Cubic Feet per Minute HVAC, ventilation

Metric Units

L/s Liters per Second Irrigation, water treatment
L/min Liters per Minute Medical, laboratory
m³/h Cubic Meters per Hour Industrial, municipal

Conversion Examples

GPM to CFS Conversion

Input 500 GPM
Formula 500 × 0.002228
Result 1.114 CFS

Practical Application Example

Scenario Irrigation System Design
Flow Required 250 GPM
Converted 0.557 CFS
Classification Low Flow

Why Units Matter

Using the wrong units can lead to serious problems:

  • Undersized Pipes: Too small diameter causes pressure loss and poor performance
  • Oversized Pumps: Unnecessarily high energy costs and equipment wear
  • Inefficient Systems: Poor water distribution in irrigation or cooling systems
  • Safety Issues: Incorrect flow rates in fire suppression or safety systems

This calculator ensures you always work with the right flow rate units for your specific application, whether you're planning a backyard irrigation system or designing a municipal water treatment plant.