The smallest carnivore on earth is the Little Weasel which is also the smallest weasel compared to the larger weasels.
The little weasel which is the smallest carnivore on earth is also known as the least weasel (Mustela nivalis), known as little weasel, common weasel, or simply weasel, is the smallest member of the genus Mustela, family Mustelidae and order Carnivora.
The largest carnivore on earth is the Polar bear.
Adult full grown Polar bears can weigh as much as 880–1,320 lbs which is way larger than most humans would ever weigh.
When it comes to the largest carnivore on earth the Polar bear tops the list and for the smallest carnivore on earth the little weasel is on the top smallest carnivores.