Airflow CFM Calculator

1. Definition

An airflow calculator converts between common ventilation flow rate units such as cubic feet per minute (CFM), liters per second (L/s), and cubic meters per second (m³/s). These units are essential for HVAC system design, fan selection, ventilation sizing, and ensuring proper indoor air quality.

2. Background Theory

Airflow is the volumetric rate of air movement through ducts, spaces, or equipment.
Common conversion relationships include:

• 1 m3/s=1000 L/s

• 1 m3/s=2118.88 CFM

• 1 CFM=0.0004719 m3/s

These conversions allow engineers to interpret equipment specifications, ventilation standards, and duct sizing requirements across metric and imperial systems.

3. How the Calculator Works

1. The user inputs an airflow value and selects the unit.

2. The calculator converts the entered value into m³/s, the base SI volumetric flow rate.

3. Using standard conversion factors, it computes:

   • CFM

   • L/s

   • m³/s

4. The final results are displayed together for easy cross-reference.

This enables quick, accurate airflow conversions during HVAC design, troubleshooting, and system evaluation.

While airflow conversion is useful for basic calculations, real HVAC engineering often requires understanding how airflow behaves inside rooms, ducts, diffusers, and ventilation systems. Simple unit conversions cannot predict pressure distribution, flow uniformity, hot or cold spots, or ventilation effectiveness. For engineers who want deeper insight into air movement and thermal distribution, tensorHVAC-Pro provides a dedicated HVAC simulation platform. Designed specifically for HVAC engineers rather than CFD experts, tensorHVAC-Pro lets you visualize airflow patterns, temperature fields, and ventilation performance with an intuitive interface and automated workflows—making advanced airflow analysis accessible without requiring CFD knowledge.