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.

What is US gallon?

A US gallon is a volume unit equal to 128 US fluid ounces, or approximately 3.785 litres. It is the standard unit for fuel, milk, and other liquid products in the United States.

Real-world uses

US gallons are used for fuel pricing and vehicle fuel economy (miles per gallon) in the United States. Milk, water, and paint are commonly sold in gallon containers. Pool volumes and water heater capacities are specified in gallons.

History

The US gallon is based on the English wine gallon of 231 cubic inches, which was defined by Queen Anne in 1707. When Britain adopted the Imperial gallon in 1824 (based on water weight), the US retained the older wine gallon standard.

Common mistakes

Confusing US gallons with Imperial gallons: a US gallon is about 3.785 litres while an Imperial gallon is about 4.546 litres—roughly 20% larger. This causes major confusion when comparing fuel economy between US and UK figures.

When is this conversion used?

Fuel economy, beverage volumes, and liquid measurements frequently require converting between litres and US gallons, especially for automotive and cooking contexts across different markets.

Worked examples

1 tablespoon (metric) = 0.00396258 US gallon

1 US gallon = 3.78541178 litre

How to convert tablespoon (metric) to US gallon

To convert tablespoon (metric) to US gallon, multiply the value by 0.00396258.

To convert US gallon back to tablespoon (metric), multiply by 252.3607856.

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: tablespoon (metric) to US gallon

tablespoon (metric)US gallon
0.10.00039626
0.50.00198129
10.00396258
20.00792516
50.0198129
100.03962581
250.09906452
500.19812904
1000.39625808
2500.9906452
5001.98129039
1,0003.96258079

Common values

tablespoon (metric)US gallon
A teaspoon0.33333333 tablespoon (metric)0.00132086 US gallon
A cup of coffee16.66666667 tablespoon (metric)0.06604301 US gallon
A water bottle33.33333333 tablespoon (metric)0.13208603 US gallon
A bathtub20,000 tablespoon (metric)79.25161571 US gallon
A swimming pool (Olympic)166,666,666.66666669 tablespoon (metric)660,430.13089537 US gallon