Air Flow & HVAC Duct Velocity Calculator
HVAC ventilation and duct sizing calculator. Computes air velocity in Feet Per Minute (FPM) and m/s, cross-sectional duct area for round spiral or rectangular ducts, and ventilation Air Changes Per Hour (ACH) with turnover times.
Air Flow & HVAC Duct Velocity Calculator
Calculate duct velocity (FPM), cross-sectional area, CFM airflow rates, and room air changes per hour (ACH).
1146 FPM
Feet per minute5.82 m/s
Meters per second0.35 sq ft
50.3 sq in🔴 High / Noisy Duct
Noise thresholdHow to Use Air Flow & HVAC Duct Velocity Calculator
Select Calculation Mode
Choose between Duct Velocity (FPM) or Room Ventilation (ACH).
Enter Airflow & Dimensions
Input CFM and duct diameter or room dimensions.
Analyze Velocity & Noise
View air velocity, metric equivalents, and noise suitability ratings.
Frequently Asked Questions
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