The metric unit for measuring weight is the gram. The gram is a very small measurement (about 0.0353 of a U.S. ounce); therefore, the base measure is the kilogram (1,000 gr or 2.2046 lb).
Prefixes are added to gram to show multiples and submultiples, just as in length. The units used most often are the kilogram, the gram, and the millligram. 

