Long ton (weight ton or imperial ton) is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. One long ton is equal to 2,240 pounds (1,016 kg), 1.12 times as much as a short ton, or 35 cubic feet (0.9911 m³) of salt water with a density of 64 lb/ft³ (1.025 g/ml). It has some limited use in the United States, most commonly in measuring the displacement of ships, and was the unit prescribed for warships by the Washington Naval Treaty 1922—for example battleships were limited to a mass of 35,000 long tons (36,000 t; 39,000 short tons).

A long ton is defined as exactly 2,240 pounds.
A pound is defined as exactly 453.59237 grams.
So a long ton is defined as exactly 1,016,046.9088 grams, which is approximately 1,016 kg.

Long may refer to:

The ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.

It is derived from the tun, the term applied to a barrel of the largest size. This could contain a volume between 210 and 256 gallons (800 to 1000 L), which could weigh around 2,000 pounds (900 kg) and occupy some 60 cubic feet (1.7 m³) of space.

In the United Kingdom the ton is defined as 2,240 pounds (1,016 kg) (avoirdupois pounds).. From 1965 the UK embarked upon a programme of metrication and gradually introduced metric units, including the tonne (metric ton), a non-SI metric unit defined as 1000 kg. The UK Weights and Measures Act 1985 explicitly excluded from use for trade many units and terms, including the ton and the term "metric ton" for "tonne".

In the United States and Canada a ton is defined to be 2,000 pounds (907 kg).