A fifth is a unit of volume formerly used for wine and distilled beverages in the United States, equal to one fifth of a US liquid gallon, ​4⁄ 5 quart, or 25 3⁄ 5 US fluid ounces (757 ml); it has been superseded by the metric bottle size of 750 ml,[1] sometimes called a metric fifth, which is the standard capacity of wine bottles worldwide and is approximately 1% smaller.

History [ edit ]

In the late 19th century, liquor in the US was often sold in bottles which appeared to hold one US quart (32 US fl oz; 950 ml) but in fact contained less than a quart and were called "fifths",[2] or commercial quarts.[3]

One fifth of a gallon was a common legal threshold for the difference between selling by the drink and selling by the bottle or at wholesale,[3][4][5] and thus the difference between a drinking saloon or barroom and a dry-goods store.

The fifth was the usual size of bottle for distilled beverages in the United States until 1980.[6] Other authorized units based on the fifth included ​4⁄ 5 pint and ​1⁄ 10 pint.[7]

During the 1970s, there was a push for metrication of U.S. government standards. In 1975, the Bureau of Alcohol, Tobacco and Firearms, in cooperation with the Distilled Spirits Council of the United States, proposed metric-standard bottle sizes to take effect in January 1979 and these standards were incorporated into Title 27 of the Code of Federal Regulations.[7][8] These sizes are 50, 100, 200, 375 (355 for cans), 500 (until June 1989),[9] 750, 1000, and 1750 ml.

See also [ edit ]