AS 1668
Duct Size Calculator
Sizes circular and rectangular HVAC ducts from design airflow and velocity for supply, return and exhaust systems.
Interactive calculator
Enter your project parameters below to calculate an indicative result.
Important guidance
This calculator provides guidance and an engineering estimate only. It does not replace project-specific design, verification or professional engineering advice. Confirm inputs, assumptions and the applicable edition of each referenced standard before relying on a result.
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