Convert chain (US survey) to millimeter Online | Free Length Converter

Chain (US Survey)

The US survey chain is a unit of length used historically in land surveying in the United States. It is defined as exactly 66 US survey feet, which is slightly longer than the international foot. Since one US survey foot equals about 0.3048006096 meters, the US survey chain is approximately 20.11684 meters long.

Like the standard chain, it is divided into 100 links, each measuring 0.66 US survey feet. The US survey chain was widely used in the Public Land Survey System to measure land parcels and boundaries.

Key facts:

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  1 US survey chain = 66 US survey feet

  
  
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  1 US survey chain ≈ 20.11684 meters

  
  
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  10 US survey chains = 1 furlong

  
  
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  80 US survey chains = 1 US survey mile

  
  

Though the US survey foot and chain are being phased out in favor of international units, the US survey chain still appears in historical land records and some legal contexts.

Millimeter

A millimeter (mm) is a very small unit of length in the metric system. It is commonly used to measure tiny objects or precise dimensions. One millimeter is equal to one-thousandth of a meter (1 mm = 0.001 m), and 10 millimeters make 1 centimeter. Millimeters are often used in fields like engineering, machining, and science where exact measurements are important. For example, the thickness of a credit card is about 1 mm. The symbol for millimeter is "mm", and you can find it on most rulers or measuring tools. Since it allows for high accuracy, the millimeter is ideal for measuring small parts, gaps, or details.