If liter is the SI unit of volume

The (sometimes also: that)[1]liter is a unit for volume and is symbolized by the unit symbol "l" or "L". The "L" was introduced as a unit symbol for the liter in order to avoid confusion with the number 1 and is more commonly used in the English and French-speaking areas. Occasionally, a small L in cursive (ℓ) is used to distinguish the unit symbol from the number 1. DIN has also adopted the neuter designation of the liter and stipulated in DIN 1301, Part 1, that the name of the unit liter should be neuterSource needed; so accordingly the Liter; like meter, radio and part, the word belongs to the nouns of double sex[2], but is much more common in the masculine.[3]

The legal unit of measurement is "liter" in addition to the SI unit of volume, the cubic meter (m3) is used. One liter corresponds to one cubic decimeter (dm3) or one thousandth of a cubic meter (1 l = 0.001 m3). A cube with an edge length of 10 cm = 1 dm therefore has a volume of one liter.


Decimal parts and multiples of the liter with their sometimes outdated designations include:

1 fl = 10−15 l
1 pl = 10−12 l
1 nl = 10−9 l
1 µl = 1 mm3 = 1 "λ" = 10−6 l
1 ml = 1 cm3 = 1 "ccm" = 1 "CC" = 0.001 l
1 cl = 0.01 l
1 dl = 0.1 l
1 l = 1 l
1 dal = 10 l
1 hl = 100 l
1 kl = 1000 l = 1 m3
1 Ml = 1000000 l = 1 dam3

The Decaliter is used in this form in German-speaking countries only in Switzerland. Kiloliters and Megaliter are uncommon; instead, cubic meters are used for calculations in these dimensions. In the beverage wholesale business, however, is the Hectoliters the usual, undeclined unit.


In 1793 the liter was introduced in France as the new "Republican unit of measurement" and equated to one cubic decimeter.

In 1879 the CIPM adopted the French liter definition and wrote the use of the l (Lower case) as a symbol.

In 1901 the liter was redefined on the third CGPM to the volume that 1 kg of pure water has at the temperature of its highest density under normal pressure (1013.25 hPa). The liter was thus about 1.000028 dm3 large (originally 1.000027 dm3 given for the conversion). Due to the new task for this unit of measurement, to couple mass and volume via a natural constant of water, pure water still had a density of 999.975 kg / m under these conditions3, but now exactly 1.0000 kg / l.

Later, the definition was set to the water temperature of 4 ° C, which is not the temperature of the highest water density (actually around 3.98 ° C). Thus, pure water again had a density slightly less than 1.0000 kg / l.

In 1964 the definition of 1793 was restored at the 12th CGPM, since then one liter has been exactly one cubic decimeter again, and water, as before 1901, has a density of 0.999975 kg / l.

In 1979, at the 16th CGPM, the liter became the alternative symbol L. (Capital letter L), at the same time the wish was expressed to keep only one of the two symbols (lower case or upper case) in the future. Most recently in 1990 it could only be determined that it was still too early to make a decision.


  1. Duden; in Switzerland exclusively m., otherwise both are used
  2. Dual gender nouns
  3. Google finds 101,000 pages with "the liter", but 584 with "the liter"

Category: Unit of Measure