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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.

Get What You Pay For: At the Grocery Store

News and Updates

Events

5615: Mass Metrology Seminar

Mon, Oct 19 - Fri, Oct 30 2020
The Mass Metrology Seminar is a two-week, "hands-on" seminar. It incorporates approximately 30 percent lectures and 70

Industry Impacts

Fare Standards for Rideshare Services

To calculate fares, app-based ride services such as Lyft and Uber don’t use traditional taxi meters, but instead combine data from GPS and cellular networks to

Projects and 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

Publications

The International System of Units (SI), 2019 Edition

Author(s)
David B. Newell, Eite Tiesinga
The definitive international reference on the International System of Units (SI) is a booklet published by the International Bureau of Weights and Measures

Awards