80億分之一 is a free life simulation game about experiencing one life from beginning to end. At the start, the game randomly determines which country and family you are born into, so every playthrough begins from a different set of circumstances. From there, players move through a sequence of meaningful choices involving education, work, relationships, migration, and other turning points in life.

The project is designed to make the uncertainty of life tangible through an interactive experience rather than a static story. Because each run is shaped by a different starting point and a different chain of decisions, players can reflect on how opportunity, context, and personal choices interact over time. The goal is not to provide a single correct path, but to let people explore how one life can unfold in many directions.

80億分之一 is presented as a simple, accessible simulation for anyone curious about life decisions, alternate possibilities, and the role of chance. It is available for free at the official website, where visitors can start a simulation and experience a one-time life journey for themselves. The product name refers to the scale of the world and the uniqueness of an individual life.

It can be explored casually or revisited to compare different outcomes.