Equivalent Duct Diameter Calculator
Calculate the equivalent circular diameter from a rectangular duct's dimensions.
How to use this calculator
What to enter
Enter or select the following as requested: Rectangular duct width (m); Rectangular duct height (m). Follow the units, valid ranges, examples, and options displayed beside each field.
What the result means
The thermal or HVAC result estimates heating, cooling, airflow, heat transfer, or efficiency from the dimensions, temperatures, rates, and equipment values entered. Check design conditions, insulation, occupancy, ventilation requirements, equipment efficiency, and the units used.
When to use it
Use this for preliminary building comfort or equipment planning. Confirm actual site conditions, manufacturer data, and applicable mechanical/building codes before sizing or installing HVAC equipment.