What is litre?

The litre is a metric unit of volume equal to one cubic decimetre. It is widely used for measuring liquid quantities in cooking, beverages, fuel, and laboratory work across metric countries.

Real-world uses

Litres are the global standard for beverage volumes, fuel tank capacities, engine displacement, and liquid medications. Water intake recommendations are given in litres (about 2 L/day), and swimming pools are measured in thousands of litres.

History

The litre was originally defined in 1795 as one cubic decimetre. In 1901 it was redefined based on the mass of water, creating a tiny discrepancy with the cubic decimetre. In 1964, the original definition (1 L = 1 dm³ exactly) was restored.

Common mistakes

Confusing litres with liters (both are correct—"litre" is the international spelling, "liter" is American). Also, assuming 1 litre of any liquid weighs 1 kg; this is only true for water at 4°C.

What is cubic metre?

A cubic metre is the SI unit of volume, equal to a cube with one-metre sides. It is used in construction, water supply, industrial gas storage, and large-scale fluid measurement.

Real-world uses

Cubic metres are used for water and natural gas billing, concrete volumes in construction, shipping container capacities, and lumber measurement. Swimming pools, reservoirs, and water tanks are specified in m³. One m³ of water weighs one metric tonne.

History

The cubic metre is an SI-derived unit following naturally from the metre. It became the standard volume unit for large quantities in engineering and commerce. Water utilities worldwide adopted it as their billing unit, replacing older local measurements.

Common mistakes

Forgetting that 1 m³ = 1,000 litres, not 100. Also, confusing cubic metres with square metres—m³ is volume while m² is area. A small error in linear dimensions leads to large volumetric errors because volume scales cubically.

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 litre = 0.001 cubic metre

1 cubic metre = 1,000 litre

How to convert litre to cubic metre

To convert litre to cubic metre, multiply the value by 0.001.

To convert cubic metre back to litre, multiply by 1,000.

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: litre to cubic metre

litrecubic metre
0.10.0001
0.50.0005
10.001
20.002
50.005
100.01
250.025
500.05
1000.1
2500.25
5000.5
1,0001

Common values

litrecubic metre
A teaspoon0.005 litre0.000005 cubic metre
A cup of coffee0.25 litre0.00025 cubic metre
A water bottle0.5 litre0.0005 cubic metre
A bathtub300 litre0.3 cubic metre
A swimming pool (Olympic)2,500,000 litre2,500 cubic metre