Convert Chain (ch) to Inch (US Survey) (in (US)) instantly.
About these units
Chain (ch)
A chain is equal to 66 feet or 4 rods, and it was standardized by surveyor Edmund Gunter in the 17th century. "Gunter's chain," consisting of 100 metal links, became the backbone of land surveying in the English-speaking world for centuries. Its convenience stems from simple arithmetic: 10 square chains make an acre, making land area calculations straightforward. Railroads, farmland, and city parcels across the United States and the Commonwealth nations were once laid out using chains, so the unit appears in countless historical records. Even today, some legal property descriptions still reference chain-based measurements, making the unit relevant for modern surveyors who interpret old maps. Although high-precision digital equipment has replaced physical chains, the unit's structural role in land division ensures its lasting importance.
Inch (US Survey) (in (US))
The US Survey Inch is derived from the US survey foot, making it exactly 1/12 of the US survey foot (~2.540006 cm). It is used in precise surveying applications where small differences can accumulate over large distances. Historically, it ensured consistency in cadastral maps, railroad engineering, and construction projects, especially when reconciling legacy measurements with modern geodetic data. Though seldom used outside surveying, the US survey inch highlights the need for consistency and precision in civil engineering and mapping applications.