Convert Square Chains to Square Thou

Convert Square Chains (ch²) to Square Thou (thou²) instantly and accurately.

Conversion Formula

thou² = ch² × 627264000000

About Square Chains

A square chain (ch²) is a surveying unit equal to the area of a square with sides of one Gunter's chain (66 feet or ~20.12 m), approximately 404.69 m². Ten square chains equal exactly one acre, making it the natural subdivision unit in traditional land surveying. The US Public Land Survey System used chains to lay out townships and sections, and square chains appear throughout old legal property descriptions and government land grants across North America. One square chain equals exactly 16 square rods.

About Square Thou

A square thou (thou²), sometimes called a square mil, is the area of a square with sides of one thousandth of an inch (0.0254 mm), equal to approximately 6.452 × 10⁻¹⁰ m². This tiny imperial unit is indispensable in precision engineering, PCB (printed circuit board) design, and manufacturing, where conductor widths, dielectric coating thicknesses, and tight machining tolerances are specified in thou. Wire insulation, thin films, and precision-stamped metal components are commonly described using this unit.

Quick Reference Table

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