The tonne is a unit of mass equal to 1,000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the short ton and the long ton. One tonne is equivalent to approximately 2,204.6 pounds, 1.102 short tons, and 0.984 long tons. The exact corresponding SI unit is the megagram, a less common way to express the same mass.