Convert Circular Inch (circ in) to Square Foot (US Survey) (ft² (US)) instantly.
About these units
Circular Inch (circ in)
A circular inch represents the area of a circle with a diameter of exactly one inch. This yields an area of approximately 0.7854 square inches. It is sometimes used in engineering, especially in the sizing of pipes, hydraulic fittings, and certain mechanical components where circular cross-sections dominate. While not as widespread as the square inch, the circular inch offers a more direct representation of the actual shape of round components, reducing the need for manual geometric conversion.
Square Foot (US Survey) (ft² (US))
The US survey square foot is defined using the US survey foot and differs minutely from the international square foot. While the difference is negligible in everyday contexts, in land surveying even tiny discrepancies matter because property boundaries, right-of-way extents, and engineering alignments may accumulate errors over long distances. Surveyors and civil engineers must interpret historical documents using survey-based values to ensure legal consistency with old plats, deeds, and boundary descriptions.