A liter (L) is a metric unit of volume equal to 1,000 milliliters, 1,000 cubic centimeters, or 0.001 cubic meters. One liter of water weighs approximately 1 kilogram. In US customary units, one liter equals about 0.264 US gallons or 33.81 US fluid ounces.

Is it spelled 'liter' or 'litre'?

'Liter' is the American English spelling, while 'litre' is the British/international English spelling. Both refer to the same unit. The SI symbol is lowercase 'l' or uppercase 'L' (both are accepted).

A liter is the volume of a cube 10 cm × 10 cm × 10 cm (about 4 inches on each side). A standard water bottle is 500 mL (half a liter), and a large soda bottle is 2 liters.

What Is a Liter? Definition, History & Everyday Examples

Definition

1 liter = 1,000 mL = 1,000 cm³ = 0.001 m³

A liter is defined as the volume of a cube that is 10 centimeters on each side. While not an official SI unit (the SI unit of volume is the cubic meter), the liter is accepted for use with SI.

Liter Conversions

Unit	1 Liter Equals
Milliliters	1,000
US gallons	0.2642
US quarts	1.057
US cups	4.227
US fluid ounces	33.814
Imperial gallons	0.2200
Cubic inches	61.024

Common Liter Volumes

Item	Volume
Water bottle (small)	0.5 L
Wine bottle	0.75 L
Standard water bottle	1 L
Large soda bottle	2 L
Car engine oil	4-5 L
Typical bathtub	300 L
Car fuel tank	40-70 L

History

The liter was introduced during the French Revolution as part of the metric system in 1795. Originally defined as the volume of 1 kilogram of water, it was later redefined as exactly 1 cubic decimeter (1,000 cm³) in 1964.

Convert volumes with our volume converter.