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Metric

Overview

NIST's work in the metric space includes

  • basic research, such as our work on the redefinition of the SI (International System of Units, commonly known as the metric system)
  • a metric program that helps implement the national policy to establish the SI as the preferred system of weights and measures for U.S. trade and commerce. The metric program provides leadership and assistance on SI use and conversion to federal agencies, state and local governments, businesses, trade association, standards development organizations, educators, and the general public.

The Research

Projects & Programs

Additional Resources Links

News

Busting Myths about the Metric System

This year will be the 45th anniversary of the Metric Conversion Act, which was signed on December 23, 1975, by President Gerald R. Ford. Normally, we celebrate by sharing metric education resources, but this year I want to use the occasion to dispel some common misconceptions about the U.S. relationship with the metric system. You’ve probably heard that the United States, Liberia, and Burma (aka

SI Prefix Progress

Discover NIST Education Resources!

Celebrate World Metrology Day on May 20

Upcoming Events