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 tablespoon (metric)?

A metric tablespoon is a volume unit equal to exactly 15 millilitres. It is widely used in cooking recipes in metric countries as a convenient measure for sauces, oils, and seasonings.

Real-world uses

The metric tablespoon (15 mL) is used in cooking recipes worldwide, particularly for oil, vinegar, sauces, and spices. It is also a common dosing measure for adult liquid medicines. Nutritional databases often list serving sizes in tablespoons.

History

The tablespoon evolved from the table or serving spoon and was adopted as a cooking measure. The metric tablespoon was standardized at 15 mL (3 metric teaspoons). In Australia, the tablespoon was standardized at 20 mL, creating a regional exception.

Common mistakes

Assuming a tablespoon is always 15 mL—the Australian tablespoon is 20 mL, and the US customary tablespoon is 14.79 mL. Failing to check which standard a recipe uses can alter the outcome of precise baking recipes.

When is this conversion used?

Converting Imperial fluid ounce to tablespoon (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 = 1.89420417 tablespoon (metric)

1 tablespoon (metric) = 0.015 litre

How to convert Imperial fluid ounce to tablespoon (metric)

To convert Imperial fluid ounce to tablespoon (metric), multiply the value by 1.89420417.

To convert tablespoon (metric) back to Imperial fluid ounce, multiply by 0.5279262.

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 tablespoon (metric)

Imperial fluid ouncetablespoon (metric)
0.10.18942042
0.50.94710208
11.89420417
23.78840833
59.47102083
1018.94204167
2547.35510417
5094.71020833
100189.42041667
250473.55104167
500947.10208333
1,0001,894.20416667

Common values

Imperial fluid ouncetablespoon (metric)
A teaspoon0.1759754 Imperial fluid ounce0.33333333 tablespoon (metric)
A cup of coffee8.79876993 Imperial fluid ounce16.66666667 tablespoon (metric)
A water bottle17.59753986 Imperial fluid ounce33.33333333 tablespoon (metric)
A bathtub10,558.52391836 Imperial fluid ounce20,000 tablespoon (metric)
A swimming pool (Olympic)87,987,699.31963512 Imperial fluid ounce166,666,666.66666669 tablespoon (metric)

Available Volume units

More Imperial fluid ounce conversions