Etruscan shrew or Suncus etruscus are the smallest mammals by weight alive today. They are found in Europe ,North America, weigh only 1.5g, and are 36–52mm long.
Kitti's hog-nosed bat or Craseonycteris thonglongyai is one of the smallest mammals of the earth that is found in Southeast Asia and weighs around 1.7grams and are 29-33mm.
African pygmy mouse or Mus minutoides are the world's smallest rodents that are found in Sub-Saharan Africa. They only weigh 3-12g and are 6-8cm long, with an additional 3-6cm length of tail.
Baluchistan pygmy jerboa are small rodents that are found in Pakistan or Afghanistan, and they weigh nearly 3.75g and are 4.4cm long, additionally have a tail of 8cm.
Long-tailed planigale or Planigale ingramiis are the world's smallest marsupials that are found in Australia, and New Guinea. They often weigh around 4.3g and are 55-65mm long.
Narrow-nosed planigale or Planigale tenuirostris are vicious predators that eat insects and small lizards, oftenly even bigger than themselves.They are found in Australia and weigh only 5.3grams and are 7.5cm long
Paucident planigale or Planigale gilesi is one of five species of planigale, that only weigh 6.9g, and 60 and 80mm long, and additionally have a tail of 55 to 70mm.