A Child Born Today Faces a 33-Year Gap in Expected Lifespan
Life expectancy at birth runs from 87 in Monaco to 54 in Nigeria. Nigeria also holds the third-largest Gen Alpha cohort, so the gap sits where the children are.
Life expectancy at birth ranges from about 87 years in Monaco to about 54 in Nigeria, a 33-year gap — and Nigeria holds the third-largest Generation Alpha cohort at about 95 million, so the shortest expectancy sits where a large share of the children are.
Life expectancy at birth runs from about 87 years in Monaco to about 54 in Nigeria. A 33-year gap, between two children born on the same day.
The number that makes it matter is the second one: Nigeria holds the third-largest Generation Alpha cohort at about 95 million. The lowest figure in the dataset is not attached to a small population.
The two ends
| Highest | Lowest | ||
|---|---|---|---|
| Monaco | 87 | Nigeria | 54 |
| San Marino | 86 | Chad | 56 |
| Japan | 85 | South Sudan | 58 |
| Malta | 84 | Central African Republic | 58 |
| South Korea | 84 | Côte d'Ivoire | 59 |
What this measure is, and is not
It is not a prediction about any child. Life expectancy at birth is a period measure: it asks what would happen to a hypothetical cohort if today's mortality rates at every age held for their whole life. They will not. Conditions change, usually for the better, across eighty years.
A child born in Nigeria today will very probably live considerably longer than 54, and the figure would still be correct as a description of conditions in 2026.
It is heavily weighted by the first five years. This is the part most often misread. A low life-expectancy figure usually means high infant and child mortality, not that adults die at 54. In many countries at the bottom of that table, a person who reaches twenty commonly lives into their seventies. The average is dragged down by deaths at the start.
That reframes the gap: it is largely a child survival gap, which is why it sits on a site about children rather than one about ageing.
Where the gap sits relative to the children
The countries at the bottom of the life expectancy table are, with some overlap, the countries with the largest and fastest-growing child populations. Nigeria has about 95 million Generation Alphas, third behind India and China. DR Congo's under-15 population is projected to grow 41% by 2040 — the fastest in the world.
So the pattern is not a small number of small countries. A substantial share of the world's children is growing up where child survival is measurably worse, and that share is increasing, because the regions still gaining children are the ones the bottom of this table is drawn from.
The one honest conclusion
Everything above is measurement. What follows from it is contested and this site does not publish it: which interventions close the gap, at what cost, and how fast, is a live argument among people with far better data.
What is not contested is the shape. The gap is large, it is concentrated in the first five years of life, and it sits disproportionately where the next generation is being born. Any global claim about "children today" that does not carry that spread is describing a subset and calling it a world.
See the full ranking at life expectancy at birth by country, the child-population projections at under-15 population change to 2040, or the regional picture at only three regions are gaining children.