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Duct Air Velocity Calculator
Convert duct dimensions and airflow into average velocity.
Enter your values
Your inputs are processed locally. Review the method and limitations before relying on the estimate.
Your result
Worked example
400×250 mm rectangular duct at 900 m³/h yields 2.5 m/s.
Frequently asked questions
Is this a professional specification?
No. It is a planning estimate based on the numbers you enter; verify manufacturer guidance and applicable standards.
Does it use live location prices or conditions?
No. Enter actual prices, weather or site inputs; there are no live data calls.