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The International System of Units (SI), 2019 Edition



David Newell, Eite Tiesinga


The definitive international reference on the International System of Units (SI) is a booklet published by the International Bureau of Weights and Measures (BIPM) and often referred to as the BIPM SI Brochure. Entitled Le Systeme International d' Unites (SI), the booklet is written in French followed by the English text. This 2019 edition of NIST Special Publication (SP) 330 is the United States version of the English text of the ninth edition of the SI Brochure (the most current) published in 2019. The 2019 edition of NIST SP 330 replaces its immediate predecessor, the 2008 edition. Together NIST SP 330 and NIST SP 811, Guide for the Use of the International System of Units (SI), provide the official interpretation of the SI for the United States.
Special Publication (NIST SP) - 330
Report Number


International System of Units (SI), Metric System, Metrology, Weights and Measures


Newell, D. and Tiesinga, E. (2019), The International System of Units (SI), 2019 Edition, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 22, 2024)
Created August 19, 2019, Updated March 16, 2021