Today, we don't use barleycorns. In 1959, the standardized the inch across the globe. It is now scientifically defined in relation to the metric system: 1 inch = exactly 25.4 millimeters (or 2.54 centimeters).
Machinists and engineers often use "thous" (one-thousandth of an inch, or 0.001) for high-precision manufacturing. Inch vs. Centimeter: A Quick Shortcut inches
Before standardized manufacturing, people used what they had on hand to measure things. In many languages, the word for "inch" is the same as the word for "thumb" (like the French pouce ). However, thumbs vary in size, which made trade difficult. To fix this, King Edward II of England proclaimed in 1324 that an inch was equal to "three grains of barley, dry and round, placed end to end." The Modern Definition Today, we don't use barleycorns
Despite the global shift toward the metric system (meters and centimeters), the inch still dominates several major industries: In many languages, the word for "inch" is
The word "inch" comes from the Latin uncia , meaning "one-twelfth." This is because an inch was originally defined as 1/12th of a foot.