A metric ton weighs 1,000 kilograms. A metric ton (t) is not part of the International System of Units but is approved for use. Ton can be spelled as "tonne," which is the standard spelling in the metric system. Prior to metrication, the ton weighed 1,016 kilograms, or 2,240 pounds.
To differentiate between the different tons, the system has come up with the long ton, tonne and short ton. The long ton weighs 2,240 pounds, the tonne weighs 1,000 kilograms (2,204.6 pounds) and the short ton weighs 2,000 pounds (907.2 kilograms). The long ton and the tonne are commonly used in the United Kingdom for trade. The short ton is used in the United States.