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Weights & measures

Overview

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

News

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

A streaked image of a taxi and a dark car driving in Times Square, New York City street at night.

New Standard Aims to Ensure Accurate Fares in Both Ride-Hailing Technology and Traditional Taxi Services

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