Before we can answer the question, we must first establish who or what a monkey is.


Monkeys are haplorhine ("dry-nosed") primates, a paraphyletic group generally possessing tails and consisting of approximately 260 known living species. Many monkey species are tree-dwelling (arboreal), although there are species that live primarily on the ground, such as baboons. Most species are also active during the day (diurnal). Monkeys are generally considered to be intelligent, particularly Old World monkeys.
- Urban dictionary

Now that we are equipped with this knowledge, we can finally create a tier list!

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