What is Imperial fluid ounce?
An Imperial fluid ounce is a volume unit used in the United Kingdom equal to approximately 28.41 millilitres. It is used in British cooking recipes, beverage servings, and pharmaceutical labelling.
Real-world uses
Imperial fluid ounces are used in the United Kingdom, Canada (in some contexts), and other Commonwealth countries for beverage serving sizes and recipe measurements. A British pint is 20 Imperial fluid ounces, compared to the US pint of 16 US fluid ounces.
History
The Imperial fluid ounce was defined by the British Weights and Measures Act of 1824, which established the Imperial gallon based on the volume of 10 pounds of water at 62°F. One Imperial fluid ounce is 1/160 of that gallon.
Common mistakes
Assuming Imperial and US fluid ounces are the same. An Imperial fluid ounce is about 28.41 mL versus 29.57 mL for the US version. This means an Imperial pint (568 mL) is larger than a US pint (473 mL).
What is teaspoon (metric)?
A metric teaspoon is a volume unit equal to exactly 5 millilitres. It is a standard unit in cooking recipes and pharmaceutical dosing instructions across metric countries.
Real-world uses
The metric teaspoon (5 mL) is used in cooking recipes, pharmaceutical dosing instructions, and nutrition labelling. It is the standard dosing spoon for children's liquid medicines. Most international recipes specify teaspoon measurements assuming the 5 mL metric standard.
History
The teaspoon originated as a unit of apothecary measure in the 18th century, roughly the volume of a small spoon used to stir tea. The metric teaspoon was standardized at exactly 5 mL to align with the metric system and simplify pharmaceutical dosing.
Common mistakes
Confusing the metric teaspoon (5 mL) with the US customary teaspoon (4.929 mL) or the older Imperial teaspoon (3.55 mL). Also, using a household spoon instead of a measuring spoon—actual spoons vary widely in size.
When is this conversion used?
Converting Imperial fluid ounce to teaspoon (metric) is useful in the volume domain when comparing values across different measurement standards or applying formulas that require a specific unit.
Worked examples
1 Imperial fluid ounce = 5.6826125 teaspoon (metric)
1 teaspoon (metric) = 0.005 litre
How to convert Imperial fluid ounce to teaspoon (metric)
To convert Imperial fluid ounce to teaspoon (metric), multiply the value by 5.6826125.
To convert teaspoon (metric) back to Imperial fluid ounce, multiply by 0.1759754.
Measurement standards
The cubic metre is the SI derived unit of volume. The litre, equal to exactly one cubic decimetre (0.001 m³), is accepted by the BIPM for use alongside SI units. Both the lowercase "l" and uppercase "L" are approved symbols for the litre.
Did you know?
An Olympic swimming pool holds 2,500 cubic metres of water — about 2.5 million litres. The Amazon River discharges roughly 209,000 cubic metres per second, enough to fill 84 Olympic pools every single second.
Quick reference: Imperial fluid ounce to teaspoon (metric)
| Imperial fluid ounce | teaspoon (metric) |
|---|---|
| 0.1 | 0.56826125 |
| 0.5 | 2.84130625 |
| 1 | 5.6826125 |
| 2 | 11.365225 |
| 5 | 28.4130625 |
| 10 | 56.826125 |
| 25 | 142.0653125 |
| 50 | 284.130625 |
| 100 | 568.26125 |
| 250 | 1,420.653125 |
| 500 | 2,841.30625 |
| 1,000 | 5,682.6125 |
Common values
| Imperial fluid ounce | teaspoon (metric) | |
|---|---|---|
| A teaspoon | 0.1759754 Imperial fluid ounce | 1 teaspoon (metric) |
| A cup of coffee | 8.79876993 Imperial fluid ounce | 50 teaspoon (metric) |
| A water bottle | 17.59753986 Imperial fluid ounce | 100 teaspoon (metric) |
| A bathtub | 10,558.52391836 Imperial fluid ounce | 60,000 teaspoon (metric) |
| A swimming pool (Olympic) | 87,987,699.31963512 Imperial fluid ounce | 500,000,000 teaspoon (metric) |
Available Volume units
More Imperial fluid ounce conversions
- Convert Imperial fluid ounce to litre
- Convert Imperial fluid ounce to millilitre
- Convert Imperial fluid ounce to US gallon
- Convert Imperial fluid ounce to cubic metre
- Convert Imperial fluid ounce to Imperial gallon
- Convert Imperial fluid ounce to US fluid ounce
- Convert Imperial fluid ounce to teaspoon (metric)
- Convert Imperial fluid ounce to tablespoon (metric)
- Convert Imperial fluid ounce to cubic centimetre