A cubic metre of pure water at the temperature of maximum density (3.98 °C) and standard atmospheric pressure (101.325 kPa) has a mass of 1000 kg, or one tonne. At 0°C, the freezing point of water, it is slightly less, 999.972 kg.
It is sometimes abbreviated cu m, m3, M3, m^3, m**3, when superscriptcharacters or markup are not available/accessible (i.e. in some typewritten documents and postings in Usenet newsgroups).
Abbreviated CBM in the freight business and MTQ (or numeric code 49) in international trade.
Multiples and submultiples
Multiples
Cubic decametre
the volume of a cube of side length one decametre (10m)
equal to a megalitre
1dam3 = 1,000m3 = 1ML
Cubic hectometre
the volume of a cube of side length one hectometre (100 m)
equal to a gigalitre
1hm3 = 1,000,000m3 = 1GL
Cubic kilometre
the volume of a cube of side length one kilometre (1,000m)
equal to a teralitre
1km3 = 1,000,000,000m3 = 1TL
Submultiples
Cubic decimetre
the volume of a cube of side length one decimetre (0.1m)
equal to a litre
1dm3 = 0.001m3 = 1L
Cubic centimetre
the volume of a cube of side length one centimetre (0.01m)
equal to a millilitre
1cm3 = 0.000001m3 = 10-6m3 = 1mL
Cubic millimetre
the volume of a cube of side length one millimetre (0.001m)