Japan Population

Japan is the clearest preview of where much of the world is heading. It has the oldest population on earth, and deaths have outnumbered births every year since the mid-2000s, so the decline now underway is driven by demographics rather than policy. Decades of fertility well below replacement, combined with historically low immigration, leave no influx of younger workers to offset it, a reality visible in shuttered rural schools and the millions of abandoned akiya houses dotting the countryside.

Japan is home to about 123 million people in 2026, the 12th largest population of any country. In Eastern Asia, where it lies, that future is driven by fertility, longevity and the movement of people across its borders. Population density stands at about 325 people for every square kilometre of land.

The peak is already behind Japan: its population maxed out at about 128 million near 2010 and is contracting. By 2050 the UN expects around 105 million people, and by 2100 about 77.0 million. The 100 million threshold was crossed near 1965.

Half of Japan is currently younger than about 49, but by 2100 the median age is projected to reach around 53, while life expectancy, near 85 years, keeps rising. A rising median age means fewer working-age people supporting each retiree over time.

At about 1.22 births per woman, Japan has one of the world's lowest fertility rates, well under the replacement level of around 2.1.

These figures follow the UN's medium variant, the most widely cited scenario. The low and high variants, driven mainly by differing fertility assumptions, fan out into a wide range by 2100, so treat each number as a central estimate rather than a precise forecast.