Convert Square Inch (in²) to Square Chain (ch²) instantly.
About these units
Square Inch (in²)
A square inch represents the area of a one-inch by one-inch square. It is indispensable in engineering, manufacturing, machine design, and consumer product specifications. Mechanical components, gasket areas, electronic device screens, and pipe cross-sections are often measured in square inches. Because imperial units are deeply rooted in American manufacturing, the square inch enables precise communication among engineers and technicians. The unit remains important in pressure measurement as well—psi (pounds per square inch) combines force and area into one of the most widely recognized engineering units worldwide.
Square Chain (ch²)
A square chain equals the area of a square one chain (~66 feet) per side, resulting in 4,356 square feet, or exactly 1/10 of an acre. This unit is closely linked to the chain, a surveyor's unit standardized by Edmund Gunter in the 17th century. Because 10 square chains make an acre, survey calculations for early colonial and American lands were extremely efficient. Square chains allowed surveyors to map and divide land rapidly using ropes or metal chains, producing a legacy seen in long, straight property lines still visible today across rural landscapes.