The U.S. has resisted the metric system for more than 50 years

Excerpt from the April 4, 1970 issue of Science News


In 1970, Australia became the 40th country to completely adopt the metric system. Now, there are only three countries in the world that don’t use it: the United States, Myanmar and Liberia.


Ten years to metric, Science News, April 4, 1970 – 

Australia is taking its first brisk steps toward conversion to a fully metric system of weights and measures over the next 10 years…. The arguments for conversion to metric in Australia have been similar to those given elsewhere: The metric system is used by countries representing 90 percent of the world’s population; three-fourths of world trade is carried out in metric measurements.


Five years into Australia’s metrication, the U.S. Congress passed the Metric Conversion Act in a bid to move the country away from an imperial system based on measures such as the foot and the pound. But the voluntary process failed to gain public support.

Some U.S. industries along with science agencies made the switch, but inconsistencies have led to mishaps. In 1999, the Mars Climate Orbiter burned up in the Red Planet’s atmosphere because of a unit mix-up between NASA and Lockheed Martin (SN: 10/9/99, p. 229). Today, only the United States, Liberia, Myanmar and a handful of island nations use versions of the imperial system.

Cassie Martin is a deputy managing editor. She has a bachelor's degree in molecular genetics from Michigan State University and a master's degree in science journalism from Boston University.

More Stories from Science News on Science & Society