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Metric

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

NIST Mise en Pratique of the New Kilogram Definition

Ongoing
Realization Since the redefinition of the kilogram, the Mass and Force Group has been intricately involved with the NIST realization of mass via the Kibble balance. By maintaining traceability to the International Prototype Kilogram (IPK) via the 2019 calibration of NIST National Prototype K20, the

Precision Electro-Mechanical Experiments (PREME)

Ongoing
NIST-4 Kibble Balance Previously called ‘the Electronic Kilogram’ Project, a major component of PREME is the realization of SI unit of mass, the kilogram, using the NIST-4 Kibble balance, the fourth generation of Kibble balances at NIST. This is accomplished through a high-accuracy comparison of

Additional Resources Links

News

Top 10 Tips for Teaching the Metric System

Calling all teachers, parents and students. It’s easy to learn the metric system — or, as it’s more formally called, the International System of Units (SI). Explore these top 10 tips for teaching the SI. Let’s begin the countdown with … 10. Make it fun! Integrating metric measurements into play activities is an easy way to motivate students to learn more, build self-confidence and transfer metric

Recorded Webinars for Weights and Measures Available On-Demand!

Update on NIST Activities for EVSE

NIST Brings Mass Measurement to the Masses

Upcoming Events

86 Metric System Education Resources

Thu, Feb 13 2025, 5:00 - 6:30pm EST
The International System of Units (SI), commonly known as the metric system, is easy to use and learn when taught using

85 Metric System Estimation

Thu, Feb 27 2025, 5:00 - 6:30pm EST
The International System of Units (SI), commonly known as the metric system, is easy to use and learn when taught using