Size Tiers are groups of different playable sharks in Hungry Shark World, each containing 3 sharks as of April 23, 2017 with the exception of the Tier XS, having only the Blacktip reef shark, and the (!!) tier, having 5 sharks.

Classes (and what they can break)

There are currently 7 different Size Tiers, each capable of breaking a new barrier (other than Xs sharks), as well as any barriers smaller sharks can break. (M sharks and up can also break land barriers [I.e. ice sheets]).