United States customary units

United States customary units are a system of measurements commonly used in the United States. The United States customary system (USCS or USC) developed from the British imperial system, which was in use in the British Empire before the U.S. became an independent country. Despite the widespread international adoption of the metric system, the United States continues to use its customary units in various aspects of daily life, including commercial, industrial, and personal use.

History

The origins of the United States customary system date back to the English units used in the British Empire before the American Revolution. After gaining independence, the United States continued to use the British imperial system, which was later standardized and became known as the United States customary system. Over the years, there have been various efforts to promote the metric system in the United States, but the customary system remains deeply ingrained in American society.

Units

The United States customary system includes units for measuring length, weight, volume, and temperature.

Length

The primary units of length in the United States customary system are the inch (in), foot (ft), yard (yd), and mile (mi). There are 12 inches in a foot, 3 feet in a yard, and 5,280 feet in a mile.

Weight

Weight is measured in pounds (lb), with smaller weights often expressed in ounces (oz). There are 16 ounces in a pound. For heavier weights, tons are used, with one ton being equivalent to 2,000 pounds.

Volume

Volume can be measured in both liquid and dry measures. Common liquid units include the teaspoon (tsp), tablespoon (tbsp), fluid ounce (fl oz), cup (c), pint (pt), quart (qt), and gallon (gal). Dry volumes, used less frequently, include dry pints, dry quarts, and bushels.

Temperature

Temperature in the United States is commonly measured in degrees Fahrenheit (°F), unlike most of the world which uses degrees Celsius (°C).

Conversion to Metric

Conversion between United States customary units and metric units involves specific conversion factors. For example, 1 inch is equal to 2.54 centimeters, and 1 pound is equal to 0.453592 kilograms. Despite the availability of these conversion factors, the use of two systems can sometimes lead to confusion in international trade, science, and engineering.

Current Use

While the metric system is used for most scientific applications, the United States customary system is still used extensively in many aspects of American life, including road signage, cooking measurements, and body weight measurements. There have been various legislative efforts to increase the use of the metric system in the United States, but the customary system remains prevalent.

See Also

• Metric system
• Imperial units
• Conversion of units