One in Eight Billion/Method
How it is calculated
Real statistics and invented rules are kept strictly apart here. The population and the mortality are real; the events you meet are not. Below is what comes from where, and which numbers are estimated.
By The author of One in Eight Billion · updated · dataset is the 2026 medium variant
One person made this: the data pipeline, the engine, the interface and the copy. Corrections to the method are welcome; every source is listed at the bottom.
How the birthplace is drawn
Birth country is drawn in proportion to each country’s births in a year, from the UN World Population Prospects 2024, 2026 medium variant. Sex is drawn from that country’s sex ratio at birth; urban or rural from its urbanisation rate; the household’s position in the income distribution from a lognormal whose spread is back-solved from the country’s Gini coefficient. You have no say in any of it — that is the design, not an omission.
About 132.5 million people are born in 2026, matching the UN’s own global total. India, China, Nigeria and Pakistan together account for roughly four in ten of them, which is why they come up most often.
How death happens
From birth, every person is tested once a year against the single-age mortality rate for that country, sex and year. The rates come from the UN’s full life table, covering ages 0 to 110. The table ends in 2023 and a life may run past 2100, so later years use a mortality-improvement factor back-solved from the UN’s life-expectancy projections — modelled, not observed.
Cause of death is sampled from age- and region-specific patterns (cardiovascular, cancers, respiratory infection, perinatal conditions, road injury and so on), weighted to resemble WHO and Global Burden of Disease distributions, but not reproduced country by country.
How income is calculated
The income distribution is lognormal, with the standard deviation back-solved from the Gini coefficient and the mean set at 0.9 times GDP per person (PPP). The same function answers both “how much does someone at this percentile earn” and “which percentile does this income fall in”. Essential spending falls as a share of income as income rises, so poorer households save less.
Where parents and background come from
Three things are drawn at birth: the household’s income position, what each parent does, and how long they stayed in school. Income position comes from the country’s distribution; parents’ work from the same labour structure, with education deciding which tier they can enter; years of schooling depend on both household wealth and the country’s education level — in a country where most people leave school at twelve, even a rich family rarely produces two graduates.
None of this carries over between runs. Every run is a fresh draw.
How the global rank is calculated
A national percentile only answers “where do I stand among my compatriots”. Answering “where do I stand among eight billion” needs a world distribution: every country’s income distribution weighted by its population, so that one function can place a single income in the world.
So the same income gets two positions, and they can be far apart — 95th at home in a low-income country can be 48th worldwide. The income used is the median of ages 25 to 65: a peak flatters almost everyone and a pension makes almost everyone look destitute, and neither represents what this person earned over a life.
This is modelled, not observed. National distributions share one lognormal assumption; the world distribution is their weighted mixture. It gives a rank in the right direction and of a plausible magnitude, but it is not a measurement of anyone’s real income.
Questions
How is the birthplace drawn?
It is weighted by each country’s births in a year. About 132.5 million babies are born in 2026 — roughly 23 million in India, 8.8 million in China, 7.6 million in Nigeria — so India comes up more than ten times as often as Korea. The deck is people, not flags: 237 countries and territories each get a share of it.
Why is the same income ranked so differently at home and worldwide?
Because the ruler changed. The national percentile compares you with compatriots; the global one mixes all 237 national distributions, weighted by population, into a single world distribution. An income in the 95th percentile of a low-income country can be the 48th worldwide. Both numbers are right; they answer different questions.
The life table stops in 2023. How are the following decades handled?
The 2023 table is the anchor. The UN’s projected improvement in life expectancy — the gain, not the level — is added, and a mortality multiplier is solved by bisection. Using the gain rather than the level avoids flattening the baseline in countries where the indicator series and the life table disagree. This part is modelled, not observed.
Are the numbers on the page real statistics?
Births, population, life expectancy, infant and under-five mortality, fertility, sex ratio at birth and single-age mortality from 0 to 110 come from the UN World Population Prospects 2024. GDP per person (PPP), Gini, out-of-pocket health spending, urbanisation, enrolment, homicide, road deaths, smoking, maternal mortality and internet use come from the World Bank WDI. Only the events and people you meet are invented. Missing indicators are filled with the median of the same World Bank region and marked “estimated” in the country table.
Do I need an account or a connection?
No. A run happens entirely in the browser, saves live in localStorage, and it keeps working offline. The memorials are the only networked part: only a life you choose to publish enters the public room; otherwise it stays on your device.
Sources
- UN World Population Prospects 2024CC BY 3.0 IGO
births, population, life expectancy by sex, infant and under-five mortality, fertility, sex ratio at birth, full life table
GDP per person (PPP), Gini, out-of-pocket health spending, agricultural employment, urbanisation, secondary and tertiary enrolment, homicide, road deaths, smoking, maternal mortality, internet use
- Natural EarthPublic domain
country borders and world map (110m / 50m), projected to paths at build time; no network at runtime
Missing indicators are filled with the median of the same World Bank region and marked “estimated” in thecountry table. No global statistic here is filled with an invented number. The dataset can be reproduced byte for byte withnpm run data:check.
Boundaries
This is a work of fiction. People, names and events are generated and correspond to no real person. It does not predict your lifespan and does not judge any country. Where death, illness or violence appear, only the outcome is shown, never the process.
Not affiliated with any work of the same or a similar name.
Site address:1in8billion.world