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SI Measurement System Chart



Elizabeth J. Benham


This publication is a colorful chart explaining the 7 base units of the SI (International System of Units) and prefix symbols, featuring the Measurement League: Guardians of the SI. The Measurement League are superheroes dedicated to the fight against uncertainty, imprecision, and inaccuracy and to improving the quality of our lives and the things we build. The League of SI Superheroes was designed to encourage students to learn about metric measurements as they consider science, technology, engineering, and mathematics (STEM) careers. SI familiarity and fluency must be developed along the STEM career pipeline to prepare the future workers with essential measurement skills.
Special Publication (NIST SP) - 304a-2017
Report Number


SI, International System of Units, Metric System, Prefix, Measurement League, SI Superheroes


Benham, E. (2017), SI Measurement System Chart, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 26, 2024)


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Created August 23, 2017, Updated March 1, 2021