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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


Photo of Used and Evacuated 20 lb Cylinders

NIST Partners with NCWM and States for a National Survey on 20 lb Cylinders of LPG (Propane)

stainless steel weights

White Cat Hair on Black Pants: International Study Measures Stability of Precision Masses to Benefit Trade

weights and measures composite image

Worth the Weight: New International Guidelines Published for Manufacturing Load Cells

Upcoming Events

5786 Fundamentals of Metrology

Mon, Jan 31 - Fri, Feb 4 2022
The 5-day Fundamentals of Metrology seminar introduces participants to the concepts of measurement systems, units

5787 Volume Metrology Seminar

Mon, Feb 7 - Fri, Feb 11 2022
The 5-day OWM Volume Metrology Seminar is designed to enable metrologists to apply fundamental measurement concepts to