Through 2026, Eevee can evolve into eight distinct Pokémon in the main series games.
These evolutions are Vaporeon, Jolteon, Flareon, Espeon, Umbreon, Leafeon, Glaceon, and Sylveon. They cover Water, Electric, Fire, Psychic, Dark, Grass, Ice, and Fairy types respectively.
Eevee's branching evolution system is unusual because different conditions produce different results. Evolution stones create several forms, while friendship, time of day, location, or a Fairy-type move can affect others depending on the game.
The number is eight, not the number of type categories Eevee can use in battle. Eevee itself is a Normal-type Pokémon, and its forms were introduced across multiple generations, from the original three evolutions in Generation I to Sylveon in Generation VI.