Prepare to be amazed:

That’s right, the three countries which are not using the metric system are Liberia, Myanmar and of course… the United States of America (via Wiki). Why is the United States so keen on preserving the imperial system? In short, Americans don’t hate the metric system – they hate change, just like the rest of world. But in an ever-connected world, can the US afford not to line up to a standard that everybody else seems to adhere to? As we’ll learn, this resistance to change comes at a cost. At the same time, change also costs.

Why the US uses the imperial system

imperial vs metric

Because of the British of course. Once the British Empire colonized North America hundreds of years ago, it brought with it the British Imperial System which itself was a tangled mess of sub-standardized medieval weights and measurements. By the time America proclaimed its independence in 1776, the former colonies had still trouble measuring uniformly across the continent. In fact, the forefathers knew this well and sought to address this problem. The first step was granting   Congress the power “to coin Money … and fix the Standard of Weights and Measures,” as stated in Article I, Section 8 of the newly formed Constitution. In 1790, secretary of state Thomas Jefferson made an analysis of the matter and felt reluctant to stir  his country towards the decimal-based metric system, at the time still a fledgling standard born in France.

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The cold relations with France didn’t help too much either. The proclamation of the metric system was made on June 22nd, 1799 at Paris with the storage in the Archives of the Republic of the physical embodiments of the standard, the prototype metre and the prototype kilogram, both made of a platinum alloy, witnessed by representatives of the French and several foreign governments and most important natural philosophers of the time. France snubbed the U.S. when it invited dignitaries from foreign countries to travel to Paris to learn about the metric system.

It’s important to note, however, that even if US representatives had traveled to Paris, they must likely wouldn’t have returned with favorable news. In 1821, after studying the various units of measurement used by the 22 states, Secretary of State John Quincy Adams determined that the U.S. Customary System was sufficiently uniform and required no changes. Most people thought actually that the metric won’t survive Napoleon’s rule. They were wrong however and by the time the American Civil War ended, most of Europe had turned metric, besides the proud British of course.

In 1866, an act of Congress, signed into law by President Andrew Johnson, made it “lawful throughout the United States of America to employ the weights and measures of the metric system in all contracts, dealings or court proceedings.” The act however was merely an act of recognition, which didn’t necessarily translate into practical use.

Following the second WWII, the world officially entered a stage still in expansion: globalization. As America was importing and exporting millions of goods, it found itself in a predicament when trading with other countries, most of whom used metric. American companies had to make twin labels, train workers and students with both systems and re-purpose thousands of machines across various industries. The costs were and still are enormous. With this in mind, some Congressmen proposed the US finally switched to metric. In 1971, the U.S. National Bureau of Standards issued a report titled “A Metric America” recommending that the U.S. transition to the metric system over the course of 10 years. In response, Congress enacted the Metric Conversion Act in 1975 to commence the conversion process. However, these good intentions were extremely poorly applied because someone had the bright idea to strip out the 10-year deadline and make the conversion voluntary. Of course, no one wanted to willingly change to metric.

Why the US doesn’t use the metric system

metric vs standard

“The metric system is the tool of the devil! My car gets fifteen rams to the hogs head and that’s the way i like it!” – Abe Simpson.

So, America really tried to switch, albeit it failed miserably. Frankly, it’s easy to see why. Switching to metric is, in a sense, like switching to another language. If you’re not American, picture this: how would you feel if your government enacted a new rule that forces you to switch to the imperial system? Yes, the metric is simpler and uses fewer units, but rational reasons aside, you’d be furious simply because you’d have to change the frame of reference you’ve been used to all your life. The UK switched to metric in 1965, and this happened only because the industry forced this. UK companies were simply having too much a hard time trading with European countries. Even 50 years later, many Britons still refuse to move entirely to metric.  Distances are still measured in miles, yards and inches, weight in pounds and stones, even pints and gallons are still used.


The US isn’t pressured by the same trading problems as the UK,however. You don’t need the metric system to measure one car made in Japan, or one iPad from China, or to sell one licence of SQL Server to Germany. Most of the food and drinks are made in the US and used there. As far as science and industry go, nowadays most work in SI units. If you’ve studied science in college, you know both systems are thought and enforced. So, for now at least, Americans are still fine without the metric though sometimes problems and confusions regarding metric can cause disasters. For instance, one conversion error between US and metric measurements sent a $125 million NASA probe to its fiery death.

“The use of two different unit systems was the cause of the loss of the Mars Climate Orbiter in 1998. NASA specified metric units in the contract. NASA and other organizations  applied metric units in their work, but one subcontractor, Lockheed Martin,  provided thruster performance data to the team in pound force seconds  instead of newton seconds. The spacecraft was intended to orbit Mars at about 150 kilometers (93 mi) altitude, but incorrect data probably  caused it to descend instead to about 57 kilometers (35 mi), burning up  in the Martian atmosphere.” – Wikipedia

In the U.S. Customary System, or the inch-pound system, more than 300 different units exist to measure various physical quantities. Many of those units use the same name but have very different meanings. On the U.S. Metric Association Web site, contributor Dennis Brownridge identifies at least nine different meanings for the unit we know as a “ton”: short ton, displacement ton, refrigeration ton, nuclear ton, freight ton, register ton, metric ton, assay ton and ton of coal equivalent. This is downright confusing even for Americans!

So, while in their day to day lives Americans might not care for the metric system, they might not for long. The country will eventually change to metric, that’s a certainty, the only question that remains is when. In 2013, Myanmar (formerly Burma)  announced it would switch to metric, leaving the US in the fine company of Liberia as the only countries in the world left who haven’t switched to metric.

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