In the UK, there are 20 imperial fluid ounces in one imperial pint. An imperial pint contains 568.26125 milliliters while an imperial fluid ounce contains 28.4130625 milliliters. This means there are exactly 20 imperial fluid ounces in one imperial pint.
Quick Summary
Here is a quick summary of how many ounces are in a pint in the UK:
- There are 20 imperial fluid ounces in 1 imperial pint
- An imperial pint equals 568.26125 ml
- An imperial fluid ounce equals 28.4130625 ml
- 20 imperial ounces x 28.4130625 ml per ounce = 568.26125 ml (1 imperial pint)
The Imperial System
The imperial system is a collection of measurement units that were used in the British Empire and are still used in some countries today. Some key imperial units of volume include:
- Imperial pint = 568.26125 ml
- Imperial gallon = 4.54609 liters
- Imperial fluid ounce = 28.4130625 ml
The imperial pint is used to measure volumes of liquids such as beer, milk, or water. Under this system, one imperial pint equals 20 imperial fluid ounces.
Origins of the Imperial Pint
The imperial pint dates back to the late 18th century in the UK. Before that time, a variety of different pint measurements were used throughout England. In 1824, the imperial pint was officially defined as equal to 20 imperial fluid ounces, which equals 568.26125 ml. This standardization helped simplify trade and commerce throughout the British Empire. The imperial system continued to be used throughout the UK until metrication in the mid-20th century.
Metric Conversions
Since the UK now uses the metric system, imperial measurements like pints are no longer the official standard. However, imperial units are still commonly used in informal settings. Here are some key metric conversions to know:
- 1 imperial pint = 568 ml
- 1 imperial gallon = 4.55 liters
- 1 imperial fluid ounce = 28 ml
To convert between imperial and metric units:
- Multiply imperial pints by 0.568 to get liters
- Multiply liters by 1.76 to get imperial pints
- Multiply imperial gallons by 4.55 to get liters
- Multiply liters by 0.22 to get imperial gallons
Converting Imperial Pints to Milliliters
Since 1 imperial pint equals 568.26125 ml, the conversion is simple:
- 1 imperial pint = 568 ml
- 2 imperial pints = 1136 ml
- 3 imperial pints = 1704 ml
To convert any number of imperial pints to milliliters, multiply the number of pints by 568.26125 or round to 568 ml.
Imperial vs. US Customary System
The imperial system differs slightly from the US customary system used in the United States. While the two systems are similar, there are some key differences in the size of gallon and pint units:
- The imperial gallon equals 4.55 liters
- The US gallon equals 3.79 liters
- The imperial pint equals 568 ml
- The US liquid pint equals 473 ml
So an imperial pint and US customary pint are not equivalent volumes. This difference is important to keep in mind when converting pint measurements between the UK and US systems.
US Customary Pints
Under the US customary system:
- 1 US liquid pint = 473 ml
- 1 US liquid quart = 946 ml (2 US pints)
- 1 US gallon = 3,785 ml (8 US pints)
There are 2 US cups in 1 US pint and 16 US cups in 1 US gallon. Cup measurements are commonly used in cooking recipes in the US.
Converting Between UK and US Pints
To convert imperial pints to US liquid pints:
- Multiply imperial pints by 0.833
For example:
- 1 imperial pint x 0.833 = 0.833 US pints
- 2 imperial pints x 0.833 = 1.666 US pints
To convert US liquid pints to imperial pints:
- Multiply US pints by 1.2
For example:
- 1 US pint x 1.2 = 1.2 imperial pints
- 2 US pints x 1.2 = 2.4 imperial pints
Pint Equivalents
Here are some common pint conversions between imperial and US pints:
| Imperial Pints | US Liquid Pints |
| 1 | 0.83 |
| 2 | 1.67 |
| 3 | 2.5 |
| 4 | 3.33 |
| 5 | 4.17 |
This table can help quickly convert pint measurements between the imperial system and US customary system.
Common Uses for Pints in the UK
Though the UK has officially adopted the metric system, imperial pints are still widely used informally in everyday life. Some common uses for pints in the UK include:
- Beer – Pints of beer are a staple of British pub culture. Beer is commonly served in imperial pint glasses.
- Milk – Milk has traditionally been sold by the pint in Britain, though metric labeling is now common.
- Cider – Like beer, cider is served in pubs by the imperial pint.
- Motor fuel – UK fuel economy is often measured in miles per imperial gallon rather than liters per 100 km.
Pints are less commonly used to measure other types of liquids like water or juice, though some older recipes may rely on pint volumes.
Pubs and Pints
One of the most enduring uses of the imperial pint is for serving beer at pubs throughout the UK. The traditional British pint glass holds 20 imperial ounces. Pints of draught beer are such an iconic pub staple that the term ‘pint’ is often used as a synonym for ‘beer’ in British slang. Ordering ‘a pint’ means a pint of draught beer unless otherwise specified.
Some pubs now serve beer in larger metric pint glasses that hold 568ml. However, the traditional 20 oz imperial pint remains the standard. British pub culture is very much built around the imperial pint of beer.
How a Pint Measure is Defined
Officially, an imperial pint in the UK is defined as exactly 20 imperial fluid ounces. This volume definition has been set in British law since 1824. To guarantee accuracy, government-approved pint glasses carry a stamped crown marking along with a ’20 fl oz’ notation.
Under British weights and measures regulations, establishments serving pints of beer, cider, or milk are legally required to use certified, correctly calibrated glassware sized to hold 20 oz. This ensures customers get a full, honest pint.
Ounce Definition
The imperial fluid ounce is formally defined as 1/160th of an imperial gallon. Since one imperial gallon equals exactly 4.54609 liters by definition, there are 160 imperial fluid ounces in 4.54609 liters. This works out to 28.4130625 ml per imperial fluid ounce.
So the exact volume of an imperial fluid ounce is defined by its relation to the imperial pint and gallon. All three measurements – ounce, pint, and gallon – are precisely interrelated.
A Pint By Any Other Name
While the imperial pint is a uniquely British unit, some other cultures have their own units also called a ‘pint’ with different definitions:
- US pint – The US liquid pint is 16 US fluid ounces (473 ml).
- Scottish pint – In Scotland, a ‘Scottish pint’ historically referred to a larger unit of approximately 1667 ml.
- Australian pint – In Australia prior to metrication, a ‘pint’ referred to a larger 565 ml unit.
So it’s important to specify which type of pint is being used. The British imperial pint has a unique 20 oz definition not equal to pints used elsewhere.
Australian and Scottish Pints
Prior to adopting the metric system, Australia historically used an imperial pint that was 565 ml, slightly larger than the modern British imperial pint of 568 ml. This was based on earlier 19th century British pint definitions.
In Scotland, a ‘Scottish pint’ was used that equaled approximately 1667 ml – much larger than the British imperial pint! This was equal to 2.5 imperial pints. However, since metrication these unique pints are no longer officially used.
Conclusion
In summary, an imperial pint in the UK equals exactly 20 imperial fluid ounces. This is equivalent to 568 ml. The imperial pint has been an official UK measurement since 1824 and remains widely used informally today, especially for serving beer in pubs. When converting between pints used in the UK, US, Australia, or Scotland, be aware they historically had different definitions.
