A Brief History of Weights and Measures
The Role of Weights and Measures in Society

People have always needed to trade with each other. The buying and selling of things is called commerce. Trade and commerce have been around as long as people have lived in societies. Societies cannot develop and grow without its citizens conducting business. No business can be conducted unless each person is sure the other person is being fair and honest. Fair and honest trade needs accurate weights and measures.


The Need for Weights and Measures

Weights and measures are some of the earliest tools used by humans.  Early units of measure come from parts of the body and people’s surroundings.

Measures of length came from the forearm, hand or finger.

Seeds, grains, and stones were used for weights.

Time was measured by periods of the sun, moon, and other heavenly bodies.


These weights and measures were not always the same.  For instance, seeds, stones, and people’s hands are different sizes.  As civilizations developed, it became necessary to make weights and measures standards to make sure people didn’t get cheated.  The standard is the one all the others have to match.

It was also necessary to have weights and measures officials.  The officials make sure everyone follows the rules and no one gets cheated.  Weights and measures officials are so important, it is believed that they were probably around before police or firefighters.

Systems of Weights and Measures

When we talk about weights and measures, we usually mean the individual units – like inch or pound. 

Examples of Units

Quarts Miles
Pounds Ounces

The system of weights and measures is the collection of units and how they relate to each other.

Example of
System of Weights and Measures:

8 fluid ounces = 1 cup
2 cups = 1 pint
2 pints = 1 quart
4 quarts = 1 gallon

The need for a single worldwide measurement system is becoming more important because there is more trade between countries.

Most of the world uses the "system international" that we call the metric system. The United States uses the "customary system" and is the only major industrialized country that does not require the metric system.

United States uses the "Customary System"


The majority of the world uses the metric system

International Standards

How can you know that the pound used to weigh your apples is the same whether you are in New York City or Los Angeles?

This is done by making sure each weights and measures standard is compared to a weights and measures standard that is even more accurate.  The weights and measures officials in California use standards that are checked against the national standards in Washington, D.C.


This is the international prototype kilogram which is kept in a building near Paris, France.

All standards in the world must match to this kilogram including the United States standards in Washington, D.C.

History of Weights and Measures in the United States

When the colonists came to North America, they brought with them the weights and measures they were used to.  This meant there were many different systems of weights and measures. After the American Revolution, the United States had measurements from England, Holland, France, and Spain .  This caused a lot of confusion.

To add to the confusion, a measurement unit in one colony may not mean the same thing in another colony.  This meant that a bushel of oats for your horse in the colony of Connecticut weighed 28 pounds, but in the colony of New Jersey it weighed 32 pounds.

Connecticut Bushel
New Jersey Bushel
28 lbs.
32 lbs.

Eventually the states developed uniform weights and measures laws and standards.  The standards are kept at the National Institute of Standards and Technology near the nation's capital, Washington, D.C.

History of Weights and Measures in California

Early California weights and measures were influenced by measures brought from Mexico and Spain.  The measurement most often used for length was the vara.  It was a wood stick that measured between 32 and 35 inches.  Because the vara and other measurements were not the same everywhere in California, this caused problems.

The California gold rush made this problem even worse. Each mining camp had its own weights and measures laws.
There was a need for standard units in measuring land and grain in agriculture and an accurate way in measuring and trading gold.

When California became a state in 1850, one of the first laws was to establish weights and measures standards.  That shows how important weights and measures are.

Today, all 58 counties in California have weights and measures officials whose job is to make sure that when you buy an item you are charged the correct price, the quantity is correct, and for some products, the quality is what you expect. The counties work with the Division of Measurement Standards to enforce weights and measures laws and regulations to protect consumers.

The Division of Measurement Standards is responsible for weights and measures in the State of California.  The Division of Measurement Standards is part of the California Department of Food and Agriculture and its headquarters is located in Sacramento.

If you have questions you would like to ask about weights and measures, you can contact the Division of Measurement Standards at their e-mail address:  dms@cdfa.ca.gov.


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