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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

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

Report of the 104th National Conference on Weights and Measures

Author(s)
Yvonne A. Branden, Tina G. Butcher, Richard A. Harshman, Lisa Warfield, Gloria D. Lee, John W. Barton
The 104th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 14 - 18, 2019, at the Hyatt Regency Milwaukee Hotel, Milwaukee

SI Base Units Relationships Poster

Author(s)
Eite Tiesinga, Kristen A. Dill, David B. Newell
This publication is a colorful poster illustrating the relationships of the International System of Units (SI) derived units with special names and symbols and

Awards