Sources
Where every number comes from.
This guide uses the developer’s own pages and country table first, the game’s cited data sources second, and its own calculations last. This page lists all three and the date they were checked.
Primary sources
These are the developer-controlled pages. If a fact about the game conflicts with anything else, these win.
| Source | Used for |
|---|---|
| 1 in 8 Billion — home screen | Birth settings, live build string, control bar, status panel, data panel, keepsake and classroom links. |
| 1 in 8 Billion — About / FAQ | Official address, release date, operator, price, refunds, age guidance, data sources, copycat domains, streaming permission. |
| 1 in 8 Billion — 172-country table | Birth share, odds, life expectancy, under-5 mortality, GDP per person for all 172 countries; the 131.9 million births figure on the home data panel. |
| 1 in 8 Billion — classroom teacher guide | Classroom mode changes, pupil privacy, class code, 40-minute lesson, worksheet, device support, early-death handling, 37 per 1,000 under-5 figure. |
| 1 in 8 Billion — terms and refunds | Operator identity, seller description, keepsake terms. |
| 1 in 8 Billion — privacy policy | Data practices referenced on the classroom page. |
Check date All primary pages were checked on 27 October 2026. The game is in beta and can change without notice. Re-check the official pages before repeating a price, a refund term or a feature.
The game’s data sources
The developer lists these sources on the game’s home screen, About page and country table. The guide repeats them as the game states them; it does not re-download or re-estimate the underlying UN, World Bank or WHO series.
| Source | Used by the game for |
|---|---|
| UN World Population Prospects 2024 | Births, population, life expectancy, fertility |
| UN IGME | Child mortality |
| WHO and UN MMEIG | Maternal mortality, tobacco, road deaths |
| UNDP and UNESCO | Education |
| World Bank | Income, inequality, health spending, internet use |
| ILO | Employment in agriculture |
| UNAIDS | HIV |
| UNODC | Homicide |
| UNICEF | Child marriage |
| World Happiness Report 2024 | Life satisfaction |
| WHO Global Health Estimates 2021 | Causes of death by region and age |
| UN WPP 2024, UN WUP 2018, Maddison 2020, UCDP/PRIO, Lee–Lee 2016 | Past and future worlds |
Estimates The developer says some missing values were estimated from regional averages and similar methods. The guide does not add precision the game does not publish.
Our calculations
These numbers are produced by the guide from the game’s table. They are labelled as calculations wherever they appear.
| Calculation | Formula / method |
|---|---|
| Regional birth shares | Sum of the 172 country shares by the region label on each official country page. |
| Nine-country half | Sum of the top nine birth shares: 50.50%. |
| Uniform-draw comparison | 100 ÷ 172 = 0.5814%, about 1 in 172. |
| Birth-weighted averages | Σ(share × value) ÷ 100 for life expectancy, under-5 mortality and GDP per person. |
| Simple country averages | Unweighted mean of the 172 rows. |
| Pace arithmetic | Seconds per year = pace × 60 ÷ life expectancy ÷ speed; session to life expectancy = pace ÷ speed. |
| Phrase value | 1 ÷ 8,000,000,000 = 0.0000000125%. |
| India-in-ten-draws chance | 1 − (1 − 0.176)^10 ≈ 85.6%. |
What we did not verify
- The exact probability weights inside individual decisions.
- The full event list and every event’s numeric effect.
- The exact numeric effect of each focus on each status bar.
- The retirement rules for every country and job combination.
- The developer’s future patch schedule.
- Any real-world outcome of playing the game.
Where the guide could not verify a detail, it says so on the page. The absence of a detail is not evidence that the detail does not exist; it is a limit of the guide.
Update and correction log
Substantive changes are recorded on the changelog. The editorial policy is on the about page. Corrections can be sent to editorial@1-in-8b.com.