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About OWM

The Office of Weights and Measures (OWM) is the oldest office at NIST, predating even the National Bureau of Standards (NBS) and the Department of Commerce. Our function, to “fix the standard of weights and measures,” is explicitly mentioned in the U.S. Constitution (Article I, Section 8, Clause 5). (See A Brief History of OWM.)

We do this by:

  • Developing documentary standards related to U.S. and international legal metrology.
  • Promoting the development of uniform and technically sound weights and measures across the United States.
  • Promoting the metric system, SI use and traceability .
  • Providing training to laboratory metrologists for the states, other national metrological institutes, and industry.

Who we are:


Created March 9, 2023, Updated March 20, 2023