Convert Rod (US Survey) (rd (US)) to Chain (ch) instantly.
About these units
Rod (US Survey) (rd (US))
The US Survey Rod equals 16.5 US Survey Feet (~5.0292 meters). Like the chain and furlong, it serves as a subdivision of larger units, maintaining consistency with historic Gunter-based measurements. Surveyors historically used rods to measure short distances, delineate boundaries, and calculate acreages. Its simple relationship to chains and furlongs made it practical for field measurements without complex arithmetic. Today, the US survey rod primarily appears in historical records, legal surveys, and when referencing pre-metric property data, providing continuity between older and modern surveying conventions.
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.