Of the living tiger subspecies, Sumatran tigers are the smallest, and Bengal tigers are the largest.
Of the living tiger subspecies, Sumatran tigers (Panthera tigris sumatrae) are the smallest, and Bengal tigers (Panthera tigris tigris) are the largest. Surprisingly, while Siberian or Amur tigers (Panthera tigris altaica) have long been thought to be the largest of the subspecies, measurements of tigers from the Russian Far East show they are currently no larger than the Bengal tigers of the Indian subcontinent.
An average Bengal tiger is about 3 meters from the tip of the nose to the end of the tail. Females are usually 8-8.5 feet, while males can grow to slightly over 10 feet. The average weight of Bengal females is 220-350 pounds, while males weigh about twice as much at 420-750 pounds.
Tigers from Sumatra and other Indonesian islands are smaller and darker with shorter hair than tigers from more northern areas. Adult males in tropical areas average 2.2 to 2.5 meters in total length (nose to tip of tail,) which is about a half meter shorter than males from northern areas, and weigh only 100 to 140 kilograms. Adult females in tropical areas weigh 75 to 110 kilograms, or roughly as much as a large leopard (Panthera pardus) or jaguar (Panthera onca).
The smaller body size of tigers from southern latitudes is likely to be due to an adaptation to the higher temperatures where heat must be dissipated, as well as a way to reduce energy needs in an environment where large ungulate prey are not readily available. Tigers in northern latitudes are larger cats and often deal with seasonally high temperatures by spending most of the day-time hours lounging half-submerged in shaded pools or streams.