How to play 1 in 8 billion: the complete guide
This guide explains, step by step, how the free 1in8B life simulation works: how a birthplace is drawn, how a life unfolds year by year, where your records live, how sharing works, and what the country numbers behind the story can — and cannot — tell you.
What is “one in 8 billion”?
1in8B is a free browser game about following a single life amongst eight billion. Every life begins with a birth you do not choose: a country is drawn at random, weighted by real demographic data. The years then arrive one by one as a story you read, and at each turning point you decide what the character pursues. It is fiction built on public statistics — a way to feel the scale of “one in 8 billion”, not a forecast of any real person's future.
Starting a life: a birth you don't choose
Open the site and start a new life — nothing to install and no account to create. Before the draw you can choose how the birthplace is weighted: by each country's annual births (the default) or by its population, using reference data covering 172 countries. You cannot pick a specific country, and starting another life draws a new birth that may land anywhere, including the same country again.
How a life unfolds, year by year
A life reads as a sequence of years. At key events you choose between options, and each option says openly what it tends to change. Four values describe the character — health, happiness, intellect and relationships — whilst country averages sit behind them as context, not personal predictions. Controls let you pause at any moment, adjust the pace, or hand choices to Auto and reread the journal afterwards. Tap a star on any moment you want to keep; kept moments return in the final review.
Where lives are saved — and what stays private
Your current life and recent completed lives are stored in this browser only. Clearing the site's storage or switching devices can lose them, so the game can export a JSON backup to import elsewhere; unfinished progress stays in the original browser. Optional Cloud Life Keep stores completed lives for revisiting from another browser — it never changes odds or lifespan. Classroom mode (?edu=1) sends no analytics at all, and analytics can be switched off on the page at any time.
Sharing a life
When a life ends you can share it: a picture card of the record, a plain link, or a short local video — a ten-second MP4 rendered on your device in the tall format social apps prefer. The game itself uploads nothing: sharing hands the file or link to the platform you pick, and the character's private details stay out of the shared text.
The country data behind the draw
Birth weights and country context come from public sources — UN World Population Prospects 2024 and the World Bank's World Development Indicators. Indicators mix reference years and some values are model estimates; every country page states its sources and limits. Compare countries, read the context, then play: the numbers set the stage, the draw and your choices tell the story.
Ready to meet the life that is yours one in eight billion times over? Start a life — it's free, and it takes a minute.
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