English units of measurement

English units of measurement are traditional non-metric units that developed in England, including the inch, foot, pound, and gallon. Their definitions and relationships have changed over time and vary across systems.

Inch: A unit of length equal to 1/12 of a foot. The inch is one of the system’s basic units of length.
Anglo-Saxon units of measurement: Units of length, land, and volume used in Anglo-Saxon England. These early measures formed part of the system’s historical foundations.
Imperial units: A system of units established by British law in 1824 and used across the British Empire. Imperial units formalized many measures inherited from England.
Metrication: The process of adopting the metric system in place of traditional measurement systems. Metrication has displaced English-derived units in many countries and industries.
Foot (unit): A unit of length equal to 12 inches. The foot anchors customary measurements of height and distance.
Magna Carta: A 1215 charter that limited royal authority and included provisions concerning standardized measures. Its clauses sought common measures across the realm.
United States customary units: The system of units commonly used in the United States, derived partly from English measures but distinct from imperial units. Its gallons and other units differ from their imperial counterparts.
International System of Units: The internationally standardized metric system built around seven base units. It provides the principal alternative for science and international standards.
Pound (mass): A unit of mass equal to 16 ounces in the avoirdupois system. The pound is the familiar customary unit for everyday mass.
Assize of Bread and Ale: A medieval English statute regulating the price and quality of bread and ale. Regulation of bread and ale depended on measures of weight and volume.

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