What is the formula to calculate the circumference of a round duct?

The formula for calculating the circumference of a round duct is derived from the relationship between diameter and circumference. The circumference (C) can be calculated using the diameter, as one complete revolution around the circle is equal to the diameter multiplied by π (pi). This relationship holds true for any circular object, including ducts.

By using the diameter directly in the formula C = π × diameter, you are effectively determining the total distance around the duct, which is essential for applications such as ensuring proper airflow, fitting components, or providing accurate measurements in design specifications.

This formula is fundamental in fields like HVAC design, where precision in duct dimensions is crucial for efficiency and functionality.