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NIST Research on the International System of Units

A history of NBS/NIST's involvement in the International System of Units (SI), including publications in the Journal of Research of NIST and its predecessors, and current work on the quantum-based SI. 

SI Research in Journal of Research of NIST

Explore papers on the International System of Units published in the Journal of Research of NIST, and its predecessors, dated 1904-2018. 

 

kilogram

The Revised SI at NIST

Explore papers on the revised International System of Units published in outside journals by NIST researchers, dated 2008-2018.

 

view of the inside of NIST-4 watt balance
Created March 26, 2018, Updated November 25, 2019