adoption of the metric system of measurements in the United States
Factsheet
Country United States
Country United States
Wikipedia
en.wikipedia.org › wiki › Metrication_in_the_United_States
Metrication in the United States - Wikipedia
3 days ago - U.S. customary units have been defined in terms of metric units since the 19th century, and the SI has been the "preferred system of weights and measures for United States trade and commerce" since 1975 according to United States law. However, conversion was not mandatory and many industries ...
Wikipedia
en.wikipedia.org › wiki › United_States_customary_units
United States customary units - Wikipedia
4 days ago - The U.S. government passed the Metric Conversion Act of 1975, which made the metric system "the preferred system of weights and measures for U.S. trade and commerce". The legislation states that the federal government has a responsibility to assist industry as it voluntarily converts to the metric system, i.e., metrification.
Videos
06:49
Why Doesn't the US Just Use the Metric System? - Cheddar Explains ...
Why the US doesn't use metric (even though it does) | Did You ...
22:36
Why Doesn't the U.S. Use the Metric System? - YouTube
19:28
The Strange (Logical) Reason Americans Refuse the Metric System ...
08:02
Why Doesn't The USA Use The Metric System? - YouTube
NIST
nist.gov › news-events › news › 2024 › 06 › reason-us-doesnt-use-metric-system
The Reason the U.S. Doesn't Use the Metric System | NIST
February 4, 2025 - NIST OWM's Elizabeth Benham was recently interviewed by National Geographic and described some of the reasons behind the U.S.'s lagged adoption of the metric system, including how a voluntary approach to adoption can slow down progress. She notes that “It’s been legal to use the metric system in the United States since 1866," and that the metric system is the nation’s preferred system of measurement for trade and commerce.
Open Textbook
opentextbc.ca › basickitchenandfoodservicemanagement › chapter › imperial-and-u-s-systems-of-measurement
Imperial and U.S. Systems of Measurement – Basic Kitchen and Food Service Management
September 4, 2015 - The only difference between the imperial system and the U.S. system is in volume measurements. Not only are the number of ounces in pints, quarts, and gallons all larger in the imperial system, the size of one fluid ounce is also different, as shown in the table in Table 7. Where you will notice this most is with any liquid products manufactured in Canada; these products will show the metric conversion using imperial measurement, but any products originating in the United States will show the conversion using U.S.
NIST
nist.gov › pml › owm › metric-si › us-metrication
U.S. Metrication | NIST
August 27, 2025 - Metrication is a term describing a shift from the use of customary measurement units to the International System of Units (SI), commonly known as the metric system. Operating with only one measurement system is ideal. Historically, two major approaches have been used to implement changes: top down (mandatory) or marketplace driven (voluntary).
US Metric Association
usma.org › wp-content › uploads › 2015 › 06 › 1136a.pdf pdf
THE UNITED STATES AND THE METRIC SYSTEM A Capsule History
International System of Units, abbreviated SI. ... European Common Market. The conversion of ... SI. The detailed U.S. Metric Study was
US Metric Association
usma.org › a-chronology-of-the-metric-system
A chronology of the metric system – US Metric Association
As a result of the Metre Convention, the US received a prototype metre and kilogram to be used as measurement standards. ... These metric prototypes were declared “fundamental standards of length and mass” in the Mendenhall Order. Since that date, the yard, pound, etc. have been officially defined in terms of the metric system.
NIST
nist.gov › pml › owm › metrication-law
Metrication in Law | NIST
February 13, 2025 - Currently, U.S. law permits the use of either the SI (International System of Units) or the U.S. customary measurement system. Although NIST is a non-regulatory agency, the adoption of SI practices is encouraged whenever possible.
iBiblio
ibiblio.org › units › usmetric.html
Units: The Metric System in the U. S.
This is the closest the U.S. has ever come to adopting a single system of measurement. Ironically, the U.S. missed two opportunities in 1832. Americans could have adopted the metric system, which was then at an uncertain point in its history; or they could have decided to align their measurements with the British Imperial measures established by Parliament in 1824 and thus created a possible alternative to the metric system in international commerce.
NIST
nist.gov › blogs › taking-measure › busting-myths-about-metric-system
Busting Myths about the Metric System | NIST
February 14, 2025 - All our measurement units, including U.S. customary units you’re familiar with (feet, pounds, gallons, Fahrenheit, etc.), are defined in terms of the SI—and mass, length, and volume have been defined in metric units since 1893!
Reddit
reddit.com › r/askhistory › why is the united states such an outlier on the metric system?
r/AskHistory on Reddit: Why is the United States such an outlier on the metric system?
September 4, 2024 -
Although the metric system is used in the United States, the primary measurements are still U.S. customary units.
Top answer 1 of 32
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It's worth noting that in the mid-20th century, the US and UK were both using imperial units. Both commissioned studies in the 60s and made dedicated pushes in the 70s to switch to metric. It looked as if both were on the same track, yet one worked better than the other. Looking back, the UK had a strong central government and a number of strong incentives, including metric units being required to integrate with the predecessor to the EU and close ties to Europe. The U.S. launched metrication in the aftermath of Watergate, meaning it was helmed by an unelected president at a time when trust in government had taken a sharp dive. The national mood was sour and people weren't in the mood to change one more thing. It's also partly an overstatement that the U.S. rejected metric when other previously-imperial countries converted completely. The U.S. is indeed legally a metric country, and in common practice there's an odd mix of units. Conversely, Canadians still tend to give their measurements in feet and pounds, some British people still give their weight in stone, and all three countries order draft beer in pints.
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Same system of government since before metric system was invented. Most of the others adopted it during / after revolutionary periods.
Reader's Digest
rd.com › knowledge › facts
Why Doesn't the United States Use the Metric System? Here's Why
July 28, 2025 - Have you ever noticed that systems of measurement tends to change when you leave the United States? Weight is typically measured in kilograms instead of pounds, distance is measured in kilometers over miles, and volume is measured in liters rather than ounces. But that’s not all: we also measure temperature in degrees Fahrenheit instead of Celsius. While most of the rest of the world uses the metric system (formally known as the International System of Units, or SI), the United States uses the U.S.
Lumen Learning
courses.lumenlearning.com › mathforliberalartscorequisite › chapter › converting-between-u-s-and-metric-systems-of-measurement
Converting Between U.S. and Metric Systems of Measurement | Mathematics for the Liberal Arts Corequisite
The U.S. system uses degrees Fahrenheit, written [latex]^\circ F[/latex]. The metric system uses degrees Celsius, written [latex]^\circ C[/latex]. The image below shows the relationship between the two systems.
YouTube
youtube.com › watch
Why Don't Americans Use the Metric System? - YouTube
If you grew up in the United States, you probably learned the United States Customary System (USCS) for weights and measures. USCS terms like inches, feet, p...
Published July 30, 2023
Khan Academy
khanacademy.org › math › cc-fifth-grade-math › imp-measurement-and-data-3 › imp-unit-conversion › v › u-s-customary-and-metric-units
U.S. customary and metric units (video)
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