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NIST's work in the metric space includes:
- basic research, such as our work on the dissemination of the SI (International System of Units, commonly known as the metric system)
- a metric program that implements 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 metrication assistance on SI use and conversion to federal agencies, state and local governments, businesses, trade associations, standards development organizations, educators, and the general public. The SI Teacher Kit is a collection of classroom instructional measurement resources available to U.S. educators.
Featured Videos
NIST Metric Kitchen: Baking Banana Bread Using the Metric System
NIST Metric Kitchen: Chocolate Chip Cookies
Pirates Plunder the Kilogram- NISTory
Measurement League
Emerging from their environmentally shielded world headquarters at NIST, these SI superheroes are dedicated to the fight against uncertainty, imprecision and inaccuracy and to improving the quality of our lives and the things we build.
The Measurement League's work is never done. They toil tirelessly behind the scenes to make sure the measurements that interweave our lives are as accurate and precise as possible.
News and Updates
Recorded Webinars for Weights and Measures Available On-Demand!
C-RMAP 2025: “That’s A Wrap!”
Classroom-Ready: NIST Releases Updated Metric Ruler and Conversion Card
BIPM 150th Anniversary Standout Poster
Blog Posts
One of the World’s Roundest Objects Is Helping to Build a Better Mass Measurement
How Low Can Temperature Go? Lord Kelvin and the Science of Absolute Zero
