GPM to CFM Calculator

Convert water flow rate in gallons per minute to cubic feet per minute.

Calculator

CFM Equivalent
0.000 CFM
Enter values above and click calculate.

How It Works

This converter is used when cross-referencing plumbing flow rates with HVAC airflow calculations, or when equipment specifications list flow in CFM but your measurements are in GPM.

CFM = GPM × 0.1337

Where:
GPM = flow rate in gallons per minute
0.1337 = conversion factor - one US gallon equals 0.1337 cubic feet
CFM = equivalent flow rate in cubic feet per minute

Commonly used when sizing hydronic coils, chilled water systems, or comparing plumbing flow rates to HVAC equipment specs listed in CFM.

Common example: A flow rate of 10 GPM is equivalent to 1.337 CFM.

Note: This conversion applies to water at standard conditions. Flow characteristics will vary with fluid temperature and pressure.