What was Pokémon’s original development title before the name Pokémon was chosen?

Pokémon’s original development title was “Capsule Monsters.”

Satoshi Tajiri first proposed a Game Boy concept based on collecting creatures and trading them through the system’s link cable. The project was initially known as Capsule Monsters, a name connected to the idea of storing creatures in capsules.

The title was reportedly difficult to register, so the project name changed during development. “Pocket Monsters” became the Japanese name, later shortened internationally to Pokémon. The final name captured the idea of portable creatures while working as a distinctive franchise title.

Capsule Monsters is therefore a development-history term, not the title of a released main-series Pokémon game. It is also sometimes confused with “Pocket Monsters,” which remains the Japanese franchise name. Game Freak and Nintendo developed the original games for the Game Boy, with the first Japanese releases arriving in 1996.