There are a total of 679 Small animals compiled and organized in this comprehensive list. The selection includes species under about 5 kg adult mass, common pets, and widespread wild species with well-established common names.

Small animals are species whose adult size or mass is notably smaller than large fauna, often under roughly 5 kg. They include mammals, birds, reptiles, amphibians, fish, and many invertebrates, showing diverse shapes, diets, and life histories. Small animals serve as companions, research models, pest controllers, or key ecological species in many habitats worldwide. Understanding their biology helps pet care, conservation, and education.

Interesting and little-known facts about Small animals:
– The world’s smallest mammal by mass, the bumblebee bat (Craseonycteris thonglongyai), weighs about 2 grams.
– The bee hummingbird (Mellisuga helenae), the smallest bird, measures roughly 5–6 cm and weighs about 1.6–2 g.
– A house mouse can breed year-round, producing several litters annually; litters commonly contain 4–8 pups.
– Lifespan varies widely: some small wild rodents live 1–2 years, while pet rabbits and guinea pigs often live 4–8 years.
– Many small species have very high metabolic rates and perform key ecosystem services like pollination, seed dispersal, and insect control.

The alphabetical index directs users to species details organized by common name and letter. Each entry shows Common name, Scientific name (binomial), Typical adult mass, Habitat, Lifespan, Conservation status, and Geographic range.