Conversion from Hectoliters to Centiliters

Information about the Hectoliter (hL)

The hectolitre is a unit of volume equal to one hundred litres, or a tenth of a cubic metre. Its symbol is hL. It is the trading unit of the drinks industry and of much of agriculture, and although almost nobody outside those trades ever writes it, within them it is the number that appears on every contract, licence and annual report.

Brewing runs on it entirely. A brewery's capacity is stated in hectolitres a year, duty is assessed on hectolitres produced, and the large international groups report annual volumes in hundreds of millions of them. A standard keg holds half a hectolitre, so the unit also happens to match the physical container the trade moves, which is part of why it stuck.

Wine regulation is written in the same terms. European appellation rules cap yield in hectolitres per hectare, a figure that does more than any other single number to define the character of an appellation, since a low cap concentrates the fruit and a high one dilutes it. Production statistics, stocks and the surpluses that periodically trouble the European market are all counted the same way.

Grain trading uses the unit in an unexpected direction. The hectolitre weight, or test weight, is the mass of grain that fills one hectolitre, and it is a standard quality specification: milling wheat is typically bought at 76 to 80 kilograms per hectolitre, and a load below the contracted figure is downgraded. The measurement works because well-filled, undamaged grain packs more densely than shrivelled grain does.

Dairy and other bulk liquids follow. Milk collection, fruit juice processing, edible oil and cider are all recorded in hectolitres, because the quantities involved are too large for litres to read comfortably and too small for cubic metres to be precise enough for duty and quality purposes.

For scale, a hectolitre is a large domestic water tank, a household bath filled about one and a half times, or a barrel of oil and a half. It converts to 22 imperial gallons or 26.4 United States gallons, and to 0.1 cubic metres exactly, which is the quickest route into SI-based calculations.

One hectolitre equals 100 litres, 0.1 cubic metres, about 26.4 US gallons, or about 22 imperial gallons.

Information about the Centiliter (cL)

The centilitre is a unit of volume equal to one hundredth of a litre, or ten millilitres. Its symbol is cL, and the lower-case cl is also used. Unlike most centi-prefixed units it has a real commercial life, because it happens to be the size that suits drink labelling, and in several countries it is the form printed on almost every bottle.

Drink containers are its main employment. In France, Belgium, Italy and Spain a wine bottle is labelled 75 cL, a beer 33 or 50 cL, a soft drink 33 cL, and a spirits miniature 5 cL. The same containers carry 750 ml and 330 ml in Britain, Germany and most of the English-speaking world, which is why identical bottles appear to bear different numbers depending on where they were filled.

Bar measures follow the same split. A standard spirit serving is 4 cL in France and 2 or 4 cL in Germany and Austria, while Britain pours 25 or 35 millilitres and the United States uses fluid ounces. European cocktail recipes are written in centilitres throughout, so a classic proportion of six parts to three to one appears as 6 cL, 3 cL and 1 cL, which reads more cleanly than the millilitre equivalents.

There is no legal difference between the forms. European Union labelling rules accept millilitres, centilitres and litres, so the choice is a matter of national typographic habit rather than of regulation. Where centilitres are used, the number on a bottle stays between one and a hundred for every ordinary container size, which is exactly the range a prefix is supposed to deliver.

The unit is also easy to picture. Ten millilitres is two teaspoons, a generous mouthful of water, or the dose measure supplied with a bottle of cough syrup. A tablespoon is one and a half centilitres, an espresso is about three, and a wine glass poured to a standard measure is twelve to fifteen.

Converting between systems needs some care because a centilitre falls between the two customary small measures. It is 0.338 United States fluid ounces and 0.352 imperial fluid ounces, so neither reads as a round number, and drink volumes converted between Europe and North America almost always end up rounded rather than exact.

One centilitre equals 10 millilitres, 0.01 litres, about 0.338 US fluid ounces, or about 0.352 imperial fluid ounces.