Convert Circular Inch (circ in) to Square Perch (perch²) 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 Perch (perch²)
A square perch is equivalent to a square rod, as "perch" was another historical name for a rod, used in various medieval and regional English measurement systems. Perches commonly appeared in church records, tithing assessments, and agricultural inventories. Because the perch was both a length and an area unit, it played dual roles in land taxation and construction. These overlapping terminologies—rod, pole, perch—reflect the organic evolution of measurement in medieval Europe, long before unified systems took hold.