Why does a British pint differ from an American pint?
Why does a British pint differ from an American pint?
If you order a pint of beer in London, you will receive noticeably more liquid than if you order a pint in New York. Specifically, a British Imperial pint is 20 fluid ounces, while an American pint is 16 fluid ounces.
The Historical Roots
Until 1824, both Britain and its American colonies used a confusing variety of measurement systems, including wine gallons, ale gallons, and corn gallons.
When the United States gained independence, it adopted the Queen Anne wine gallon (defined as 231 cubic inches) as its standard liquid measure. This is the foundation of the modern US liquid pint, which is one-eighth of that gallon (approx. 473 milliliters).
The 1824 British Standardization
Meanwhile, the British Parliament decided to clean up its own measurement chaos. The Weights and Measures Act of 1824 abolished the old varied gallons and introduced the Imperial system.
Instead of tying the gallon to wine, Britain defined the new Imperial gallon by the weight of water: exactly 10 pounds of distilled water at a specific temperature. This created a gallon of 277.42 cubic inches. Consequently, the British Imperial pint—one-eighth of this new gallon—came out to roughly 568 milliliters.
Summary of Differences
- US Pint: 16 US fluid ounces (~473 ml)
- British Imperial Pint: 20 Imperial fluid ounces (~568 ml)
Because the US standardizes on the older wine gallon and the UK standardized on a larger water-weight system, British drinkers have enjoyed a slightly more generous pint for nearly two centuries.