In Niger, half the population has not yet turned 16. Line up every Nigerien from oldest to youngest and the midpoint lands before a person is old enough to drive in most countries. That single number, the median age, is the cleanest way to compare how young a country’s population actually is, and a small cluster of countries, nearly all of them in Sub-Saharan Africa, sit at levels the rest of the world left behind two generations ago.
Median age is not the only way to measure a young population. The percentage of residents under 15 tells a related but distinct story, since a country can have a moderately low median age while still carrying an unusually large share of children if fertility has stayed high for a long stretch. Both measures point toward the same region of the world, but for different reasons worth separating out. A country’s median age reflects its entire population’s distribution, including working-age and older residents, while the under-15 share isolates just the youngest cohort. Together they give a fuller picture than either figure would alone.
Youngest Countries in the World
| Country | Median Age (approx.) | Population (approx.) | Share Under 15 | Total Fertility Rate |
|---|---|---|---|---|
| Niger | 15.1 years | ~27 million | ~47% | ~6.7 children/woman |
| Central African Republic | 14.5 years | ~5.7 million | ~48% | ~5.8 children/woman |
| Chad | 15.7 years | ~19 million | ~46% | ~5.9 children/woman |
| DR Congo | 15.8 years | ~102 million | ~45% | ~5.9 children/woman |
| Somalia | 16.6 years | ~18 million | ~45% | ~5.9 children/woman |
| Mali | 17.0 years | ~23 million | ~44% | ~5.6 children/woman |
| Angola | ~16 years | ~37 million | ~44% | ~5.1 children/woman |
| Uganda | ~16 years | ~48 million | ~43% | ~4.7 children/woman |
Figures are approximate estimates compiled from UN World Population Prospects 2024 Revision data as reported by StatisticsTimes and related demographic trackers; exact rankings shift slightly between sources and annual updates.
For scale, the global median age sits at roughly 31 years, meaning the youngest countries on this list have a median age barely half the world average. In Niger and the Central African Republic, an equal number of people are older and younger than a typical American high school freshman.
Why Are These Countries So Young?
- High fertility: every country on the youngest-population list has a total fertility rate well above the global average of 2.25, several sitting close to or above six children per woman.
- Larger family sizes: high fertility is often reinforced by cultural, economic, and religious factors that favor larger households, particularly in rural areas.
- Lower median age at first birth: women in these countries typically begin childbearing earlier than the global average, compressing generational spacing and keeping the population skewed young.
- Falling but still relatively high mortality: child mortality has declined substantially in nearly all these countries over the past three decades, meaning more of each large birth cohort survives into childhood and beyond, widening the youth-heavy base of the population.
- Population momentum: because these countries already have such large child and youth cohorts, total population will keep growing for decades even if fertility falls sharply starting today, simply because so many future parents have already been born.
Why Africa Dominates the Youngest Population Rankings
Sub-Saharan Africa accounts for the overwhelming majority of the world’s youngest countries. Of the roughly 25 countries with a median age below 18, nearly all sit in this single region.
This concentration reflects where each country sits in the demographic transition, the four-stage framework demographers use to describe how societies move from high fertility and high mortality toward low fertility and low mortality. Much of Sub-Saharan Africa remains in the second and third stages: mortality has fallen substantially over the past 50 years thanks to vaccination campaigns, improved maternal healthcare, and better access to basic medicine, but fertility has not fallen nearly as fast, leaving a wide gap between births and deaths that keeps population growing quickly and skewing young.
Within Africa, patterns vary considerably. West and Central African countries, including Niger, Chad, and the Central African Republic, tend to show the highest fertility and youngest populations on the continent. East African countries such as Kenya and Ethiopia have seen faster fertility declines in recent decades, producing somewhat older, though still young by global standards, population structures. Southern Africa, led by South Africa, sits closer to the global median age than the rest of the continent, reflecting a longer and more advanced fertility transition tied to differences in education, urbanization, and economic development across the region.
Outside Sub-Saharan Africa, the youngest populations cluster in the Middle East, South Asia, and parts of the Pacific. Afghanistan, Palestine, Timor-Leste, and Papua New Guinea all post median ages in the roughly 19 to 22 year range, notably older than the youngest African countries but still well below the global average. Europe’s youngest populations, by contrast, sit in an entirely different range: Kosovo, the youngest country on the continent, has a median age near 32, still ten to fifteen years older than most of the countries topping this list.
The Economic Opportunity of a Young Population
A young population is not simply a challenge. Under the right conditions, it represents one of the most powerful economic assets a country can have, and several of today’s wealthiest economies rode exactly this dynamic through their own fastest-growing decades.
- Expanding workforce: today’s large child and youth cohorts will become tomorrow’s working-age population, potentially fueling decades of labor force growth just as many aging economies see their workforces shrink.
- Demographic dividend: economists use this term to describe the growth boost a country can capture when its working-age share rises relative to dependents, a pattern several fast-growing Asian economies rode through the late 20th century.
- Consumer growth: a young, growing population represents an expanding base of future consumers, workers, and entrepreneurs, an attractive prospect for long-term investment.
- Urbanization: young populations are driving rapid city growth across Sub-Saharan Africa, creating new economic hubs and labor markets.
- Entrepreneurship: many of these countries already show high rates of informal and small-business entrepreneurship among youth, out of necessity as much as opportunity.
The Challenges of a Young Population
The same demographic weight that creates opportunity also creates enormous near-term pressure on institutions built for much smaller populations, and the timeline for building that capacity is measured in years, not decades, since these cohorts are already born and aging into each new stage of need.
- Education demand: countries with the youngest populations must build and staff schools fast enough to keep pace with cohorts of children far larger than those born a generation earlier.
- Employment demand: each large youth cohort eventually needs jobs, and economies in many of these countries are not yet generating formal employment at a matching pace.
- Healthcare: maternal and child health services face constant strain in countries where a third or more of the population is under 15.
- Housing: rapid urban population growth is outpacing housing construction in many fast-growing African cities.
- Infrastructure: roads, electricity, and water systems built for smaller populations are being stretched by rapid growth.
- Youth unemployment: several of the world’s youngest countries also report some of the highest youth unemployment or underemployment rates globally, a gap between population growth and job creation that carries real social and political risk if left unaddressed.
How Young Countries Will Change
None of today’s youngest countries will stay this young indefinitely. Fertility is already declining across nearly every country on this list, just from a very high starting point and at varying speeds.
- Fertility decline: total fertility rates across Sub-Saharan Africa have fallen measurably over the past two decades, even in the highest-fertility countries, though the pace of decline varies by country.
- Rising median age: as fertility falls, each new birth cohort becomes somewhat smaller relative to the ones before it, gradually raising the median age.
- Growing working-age population: the large child cohorts already alive today will move into working age over the coming 10 to 20 years, producing rapid growth in the labor force regardless of what happens to fertility from here.
- Future aging: later in the century, today’s youngest countries will themselves begin aging, following the same broad trajectory that Europe, East Asia, and North America have already completed, just several decades behind.
Youngest Countries Versus Oldest Countries
| Comparison Point | Youngest Countries (e.g. Niger, CAR, Chad) | Oldest Countries (e.g. Japan, Italy, Monaco) |
|---|---|---|
| Median age | ~14 to 17 years | ~48 to 57 years |
| Total fertility rate | ~5 to 7 children per woman | ~1.0 to 1.4 children per woman |
| Population growth rate | Among the fastest in the world | Flat or negative in most cases |
| Youth dependency | Very high, driven by large child cohorts | Low |
| Old-age dependency | Very low | Very high, driven by large retiree cohorts |
| Workforce trajectory | Rapidly expanding over coming decades | Shrinking without offsetting immigration |
The contrast is close to a mirror image. Where the youngest countries face pressure to build enough schools and jobs for an expanding population, the oldest countries face pressure to fund pensions and healthcare for a shrinking working-age base supporting a growing number of retirees. Both sets of pressures stem from the same underlying demographic transition, just viewed from opposite ends of the process. Over the coming decades, that gap is not expected to close on its own. Fertility is falling in the youngest countries, but from such a high starting point that median ages there will remain well below the global average for at least another generation, even as the oldest countries continue aging further still.
Frequently Asked Questions
1. Which country has the youngest population in the world?
Niger, with a median age of roughly 15.1 years, based on recent UN World Population Prospects 2024 data.
2. Why does Niger have such a young population?
Niger has the highest total fertility rate in the world, estimated at around 6.7 to 6.9 children per woman, which produces a very young age structure.
3. What percentage of Niger’s population is under 15?
Approximately 47 percent, meaning nearly half the country’s population has not yet reached its teenage years.
4. Are all of the world’s youngest countries in Africa?
Nearly all of them. Of the roughly 25 countries with a median age below 18, the large majority sit in Sub-Saharan Africa.
5. What is the youngest country or territory outside Africa?
The Gaza Strip and West Bank in Palestine and Afghanistan rank among the youngest populations outside Sub-Saharan Africa, with median ages in the range of 19 to 22 years.
6. What is the global average median age for comparison?
Approximately 31 years, roughly double the median age of the world’s youngest countries.
7. What is a demographic dividend?
The period of faster potential economic growth a country can experience when its working-age population share rises relative to its dependent population, assuming jobs and education keep pace.
8. Will young countries like Niger and Chad stay young forever?
No. Fertility is already declining in these countries, and median age is expected to rise gradually over the coming decades as birth cohorts shrink relative to earlier ones.
9. How does a young population affect economic growth?
It can boost growth by expanding the future workforce and consumer base, but only if education, job creation, and infrastructure investment keep pace with population growth.
10. What is the difference between median age and percentage under 15 as measures of a young population?
Median age describes the midpoint of the entire population’s age distribution, while percentage under 15 measures only the size of the child population relative to the total, and the two can rank countries slightly differently depending on the shape of each population’s age structure.
Sources
- United Nations, World Population Prospects 2024 Revision, Population Division, Department of Economic and Social Affairs
- StatisticsTimes.com, median age by country compilations based on UN WPP 2024
- World Population Review, “Children in the World by Country”
- Visual Capitalist, “Ranked: Countries With the Most Children in 2025” and “Map: The World’s Oldest and Youngest Countries, by Median Age”
- Statista, “Median Age in Africa” and “Youngest Countries/Territories by Median Age”
- PopulationPyramids.org, “Median Age by Country”
