Eevee has eight different evolutions in the Pokémon video game series.
These evolutions are commonly called Eeveelutions: Vaporeon, Jolteon, Flareon, Espeon, Umbreon, Leafeon, Glaceon, and Sylveon. Together, they cover eight Pokémon types introduced across multiple generations.
Eevee began with three possible evolutions in the first generation: Vaporeon, Jolteon, and Flareon. Espeon and Umbreon arrived in the second generation, while later games added Leafeon, Glaceon, and Sylveon.
The number is sometimes misstated because Eevee itself also has regional and special forms in later games. Those forms are not additional evolutions, so they do not change the total of eight.