Metric System Day

Metric System Day is an American holiday dedicated to the metric system of units. These are standardized parameters that we actively use in everyday life to describe things around us and to characterize phenomena. They include kilograms, meters, liters, and degrees (temperature). The holiday is celebrated annually on April 7.

History

The history of the metric system begins in the late Middle Ages. In 1586, the mathematician Simon Stevin published his predictions about the active use of decimals in the future. At that time, his research did not find much resonance in society, but in the 18th century, the world saw the correctness of his predictions. In 1799, Napoleon approved the metric measuring system. However, after losing the Battle of Waterloo and the end of Napoleon’s reign, many parts of Europe returned to the old units of measurement. From the late 1830s, the metric system began to gain popularity, and by the end of the 19th century, many countries in the world were already using it.

In 1866, a law was passed in the United States that allowed citizens to choose for themselves which measurement units they wanted to use: metric or the old imperial units. Therefore, in America, weight is often measured in pounds, and distance in feet and miles.

Interesting Facts

• In addition to the United States, the dual system of measurement is also used today in Great Britain. It was introduced there in 1897.
• Prefixes (kilo, milli, nano, etc.) are used to describe various numerical values.
• The metric system was initially most widespread among merchants and scientists.

How to Celebrate

Take various measurements using the metric system. Determine how long your room is, how many liters of water are in the kettle, and more. Find out more information about the metric system in different countries.

Spread the word about the holiday on social media. Ask users which system they use: modern metric or old imperial?

When is Metric System Day in 2025?

Metric System Day is observed on April 7 each year.

Observations