The metric system is unequivocally better than the customary system of measurement used in the United States.

First, the metric system is a lot easier to use. By one estimate, metric calculations can be completed 45% faster. Using the metric system also leads to fewer mistakes. The metric system is a decimal system, meaning that all conversion factors are multiples of ten. Standard prefixes such as “kilo” for one thousand and “centi” for one hundredth are used with every unit. For example, there are 10 millimeters in a centimeter, 10 centimeters in a decimeter, 10 decimeters in a meter, 10 meters in a decameter, 10 decameters in a hectometer, and 10 hectometers in a kilometer.

Meanwhile, the customary system, if it can even be called a system, is a hodgepodge of different units with many different conversion factors. For example, when measuring length, there are 12 inches in a foot, 3 feet in a yard, and 1760 yards in a mile. Meanwhile, the conversion factors for measuring weight and capacity differ. There are 8 fluid ounces (not to be confused with the avoirdupois ounces or troy ounces, two other obsolete units) in a cup, 2 cups in a pint, 2 pints in a quart, and 4 quarts in a gallon.

Second, metric units are the same all around the world. Metric measurements are set by the International Bureau of Weights and Measures, and thus don’t vary between countries. This has benefits for everything from international trade to scientific and military cooperation.

This can be contrasted with the U.S. customary system which contains several units such as the fluid ounce, pint, quart, and gallon which share names with units in the British Imperial system but differ substantially in value. For example, the British imperial gallon is 4.54 liters while U.S. customary gallon is only 3.78 liters.

For these reasons, the majority of the world’s countries have adopted the metric system. According to the CIA World Factbook, only Myanmar, Liberia, and the U.S. have not officially adopted the metric system.

Although the U.S. has not officially adopted the metric system, the metric system is still used in a large and increasing number of fields. The metric system is used almost exclusively in the science, healthcare, electronics, and automobile industries. The metric system is also used by many government departments and the military.

This is because using the metric system makes it easier for American companies to compete and work with companies in other countries. By using the metric system, companies can make products for a single set of specifications, allowing them to save money or enter new markets. It also allows companies to rethink different parts of their operations, which often leads to more logical processes and cost savings.

However, the use of two systems of measurement inflicts several large costs on society.

One of the largest of these costs is on education. Because both the metric and customary systems are used in the U.S., both systems are taught in schools. According to one study, teaching only the metric system would save about 71 days in the classroom and $1.76 billion. It is worth noting that this cost saving is several times larger than what it would cost to replace all of the customary road signs in the U.S.

Another large cost is the mistakes that stem from the use of two measurement systems. 

Perhaps the most famous incident is the crash of the Mars Climate Orbiter. One contractor, Lockheed Martin, created software that produced results in pound-force seconds while another piece of NASA software expected results in newton-seconds. As a result, the $327.6 million probe crashed into Mars’ surface.

Tragically, some mistakes can be dangerous or even deadly. One of these mistakes that happens far too often is medication errors. Medication errors contribute to about 7,000 to 9,000 deaths every year. Often, medication errors occur when different units are confused with each other. For example, the Institute for Safe Medication Practices has received 50 reports of patients confusing milliliters with teaspoons. Mistakes can also occur when patients are weighed in pounds but have their weight recorded in kilograms, which leads to patients receiving more than twice the correct dose.

Realizing the benefits of the metric system, President Gerald Ford signed the Metric Conversion Act in 1975. However, the act made metrication voluntary, and President Ronald Reagan abolished the United States Metric Board, which was responsible for coordinating the transition, in 1982. As a result, the U.S. has been trapped using two measurement systems (one vastly better than the other) for over four decades, preventing it from enjoying the benefits of metrication but not the confusion. It’s time to finish the job.