Cubic centimetres to millilitres:
they are equal

How many ml are in a cc?

One cubic centimetre is exactly 1 millilitre. The two names describe the same amount of space: a cube measuring 1 cm on each side holds 1 ml. So 1 cc is 1 ml, 50 cc is 50 ml, and 500 cm³ is 500 ml.

The reason is the way the litre is built. A litre is 1,000 cm³, and a millilitre is one thousandth of a litre, so the two cancel out and the conversion factor is exactly 1. This also means the chart below is the shortest in the series: the left and right columns match.

The cc to ml formula

Because the factor is 1, the only conversion worth doing is the next step up. Divide by 1,000 to reach litres, or multiply litres by 1,000 to reach cm³.

Chart: cm³ to ml and litres

At the top of the chart, 1,000 cm³ is 1,000 ml, which is one litre. A 1,500 cc car engine is therefore 1,500 ml, or 1.5 litres, which is how the same engine is sometimes badged as a 1.5.

Where you will meet cc and ml

Engines are rated in cc almost everywhere, from scooters to cars. Medicine syringes and some dosing droppers are marked in cc in older or informal use, and a 5 cc syringe holds 5 ml. Aquarium and laboratory glassware use ml, while product specifications for small tanks and bottles may still say cm³.

Pour a measured 250 ml into a container and you have poured 250 cm³. Water makes this easy to picture, because 1 ml of water has a mass of about 1 gram at room temperature.

More examples: aquariums, bottles and bikes

Cubic centimetres are handy when you measure a container with a ruler. A small aquarium measuring 40 cm × 25 cm × 30 cm has a volume of 30,000 cm³. Because each cm³ is one ml, that is 30,000 ml, or 30 litres. The same shortcut works for any box: multiply the three sides in centimetres and read the result as millilitres.

The idea also runs the other way. A 750 ml bottle takes up 750 cm³, and a 650 cc motorcycle engine is 650 ml, or 0.65 litres. When two figures in different units still look suspiciously similar, check whether they are really just cc and ml describing the same space.

Common mistakes with cc and ml

• Looking for a factor of 10 or 1,000 between cc and ml. There is none; the numbers are equal.
• Confusing cc with cl. A centilitre (cl) is 10 ml, so 1 cl is 10 cc.
• Confusing cubic centimetres with cubic metres. One m³ is 1,000,000 cm³, not 1,000.
• Reading 'cc' on an engine as litres. A 1,000 cc engine is one litre, not one thousand.