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Weights & measures


NIST works to improve the accuracy of measurements, enhance consumer protection, foster fair competition, and facilitate economic growth and trade through technical activities that promote uniformity in national and international legal metrology laws, regulations, standards, test procedures and enforcement.

The Research

Projects & Programs

International System of Units (SI)

The International System of Units (SI) provides definitions of units of measurement that are widely accepted in science and technology and which set measurement

Additional Resources Links


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The Future is Charged: National Electric Vehicle Infrastructure (NEVI) Formula Program

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We're Back... OWM Welcomes Laboratory Metrology Students to Campus!

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Discover NIST Education Resources!

Upcoming Events

5797 Fundamentals of Metrology

Mon, Jun 27 - Fri, Jul 1 2022
The 5-day Fundamentals of Metrology seminar is an intensive course that introduces participants to the concepts of

5799 Advanced Mass Seminar

Mon, Jul 11 - Thu, Jul 21 2022
The 9-day, hands-on Advanced Mass calibration seminar focuses on the comprehension and application of the advanced mass