Data & method
In 1975, 1,901,440 babies were born in Japan. Just as they finished university, they ran into the job-market "ice age", when only about half of new graduates found work. 1975 is a simulation that lets you be born again as one of that generation.
You start as someone born in 1975, but you can pick any year from 1947 to 2024 on the birth chart, or let fate choose. Once the year is set, your prefecture is drawn in proportion to that year's births. Your parents' education and income, schooling, work, marriage, caring for family and death are all decided by how often they happened to people of the same era and circumstances. At the end, an AI (Cloudflare Workers AI) writes a biography from the record of that life.
Four classmates born in the same year and prefecture live out their lives under the same statistics. Side by side, you can see how much the family and era you were born into shape a life, as much as talent does.
The English version currently covers the pages around the game and the biography. The events during a life are still shown in Japanese; we are translating them next.
Statistics used
| Birth year and prefecture | Births from Vital Statistics (Ministry of Health, Labour and Welfare). The split across prefectures is approximated from census population and fertility-rate trends. |
|---|---|
| Life expectancy and cause of death | A Gompertz–Makeham mortality curve fitted to the complete and abridged life tables, adjusted with the prefectural life tables. Causes of death are weights rounded from the Vital Statistics rankings by age group. |
| Family background | Parents' education from the enrollment rates of the parents' generation; family businesses from the share of farming and self-employed households; number of siblings from completed fertility. |
| Schooling | High school, university, junior college and vocational school enrollment rates by sex (School Basic Survey), adjusted for prefecture, parents' education and household income. |
| First job | Graduate employment rates (School Basic Survey), the Recruit Works Institute's job-openings-to-applicants ratio for graduates, and the general job-openings ratio. |
| Income | Trends by age, education, company size and sex from the Basic Survey on Wage Structure, converted to each year with the nominal wage index. |
| Non-regular work and job changes | The share of non-regular employment from the Labour Force Survey. In crisis years (1974, 1998, 2009, 2020 and others) the chance of losing a job rises. |
| Marriage, children and divorce | Never-married rate at 50 and average age at first marriage (Vital Statistics); the share of arranged marriages and completed fertility (National Fertility Survey). |
| Care and pensions | Long-term care certification rates (Long-Term Care Insurance reports) and rough benefit levels for employee and national pensions. |
| Prices | A bowl of ramen, a postcard stamp, a graduate's starting salary (Retail Price Survey and Basic Survey on Wage Structure). |
On accuracy
Figures are rounded from statistical tables and interpolated between years. Each probability is a guide for reproducing trends, not the table itself. From 2025 onward, the simulation follows assumptions based on the National Institute of Population and Social Security Research's projections. It is tuned so that across thousands of simulated lives, university enrollment, marriage rates, regular employment of new graduates and life expectancy come close to the real statistics.
Difficult events
Illness, disasters, divorce and suicide happen at the rates the statistics show. They are not described in detail. If you are struggling right now, please reach out to a local crisis line. In Japan, TELL Lifeline offers support in English (03-5774-0992).
Your data
Your progress is saved only in this browser. The biography, a summary of the life and the share image are stored on our server only when you create a share link.