Conversion from 3 Deciliters to Cubic inches

Information about the Deciliter (dL)

The decilitre is a unit of volume equal to one tenth of a litre, or one hundred millilitres. Its symbol is dL, and the lower-case dl is common. Although the deci prefix has fallen out of use almost everywhere else, the decilitre is alive in two quite separate places: the Nordic kitchen and the clinical laboratory.

Scandinavian cooking is built on it. Swedish, Norwegian, Danish and Finnish recipes give flour, sugar, milk, cream and stock in decilitres, and a set of nested measuring cups marked in decilitres and fractions of one is standard kitchen equipment. Where an English recipe says a cup and an Italian one weighs the flour, a Nordic recipe asks for three decilitres, which is both faster and more repeatable than either.

Switzerland uses it for drink. Wine in a Swiss restaurant is ordered by the decilitre, so a glass is one or two and a carafe five, and the measure is printed on the glass. Because a decilitre is close to the volume of a modest wine pour, the unit gives customers an exact quantity rather than a description, which is what licensing law in several cantons requires.

Clinical chemistry is its other stronghold, and there it decides how a whole country reads its blood tests. Glucose, cholesterol and creatinine are reported in milligrams per decilitre in the United States, Japan, France, Italy and Spain, and in millimoles per litre in Britain, Canada, Australia and the Nordic countries. A fasting glucose of 100 milligrams per decilitre is 5.6 millimoles per litre, and the same person's result therefore looks entirely different depending on the laboratory.

Haemoglobin crosses the divide. It is reported in grams per decilitre almost everywhere, so a normal adult value of 13 to 17 grams per decilitre reads the same in most of the world. The decilitre survives in these places because a hundred millilitres of blood is a convenient reference quantity and because changing an established reporting unit risks misreading a result.

For scale, a decilitre is a small glass of water, half a mug of coffee, or the volume of a large egg and a half. It converts to 3.38 United States fluid ounces or 3.52 imperial fluid ounces, and to a little under half a United States cup, which is why converted Nordic recipes rarely come out in round numbers.

One decilitre equals 100 millilitres, 0.1 litres, about 3.38 US fluid ounces, or about 3.52 imperial fluid ounces.

Information about the Cubic inch (in³)

The cubic inch is a unit of volume equal to 16.387064 cubic centimetres exactly. Its symbol is cu in, sometimes written in³. It is the volume of a cube one inch on each side, and 1728 of them make a cubic foot. Its most consequential role is legal rather than descriptive: the United States gallon is defined as exactly 231 cubic inches.

That definition is the reason American liquid measure is the shape it is. The figure of 231 comes from the English wine gallon standardised under Queen Anne in 1707, which the United States kept when Britain replaced its own gallons with a single imperial gallon in 1824. Every American fluid ounce, pint and quart descends from that one number, and it is why the two gallons differ by a fifth.

Engines made the unit famous. American car engines were quoted in cubic inches until the 1980s, and the numbers became names in their own right: a 350 is 5.7 litres, a 426 is 7.0, and a 302 is 4.9. Motorcycles still carry both figures, and the conversion is worth knowing, since 61 cubic inches make a litre.

Machinery uses it for swept volume. Pump and compressor displacement per revolution, hydraulic cylinder volume and metering pump strokes are all specified in cubic inches in American engineering, because the bores and strokes that produce them are already in inches and squaring or cubing an inch keeps the calculation in one system.

Freight pricing uses it in an unexpected way. American parcel carriers calculate a dimensional weight by dividing the package volume in cubic inches by a fixed divisor, commonly 139, to obtain a chargeable weight in pounds. A light bulky parcel is therefore priced by its cubic inches rather than by what it weighs, which changes how goods are packed.

The conversion to metric is exact but unhelpful. Because the inch is defined as exactly 2.54 centimetres, a cubic inch is exactly 16.387064 cubic centimetres, and no rounding is involved. That precision does not make the number easier to use, and it is the main reason engineering drawings outside the United States moved to millimetres.

One cubic inch equals 16.387 cubic centimetres, about 0.0164 litres, about 0.554 US fluid ounces, or 1/1728 of a cubic foot.