The African Century: Why Most of This Century’s Growth Happens in Africa

By the populationclock.org team · Published September 7, 2026 · All figures: UN World Population Prospects 2024, medium variant

The short answer

Africa holds about 1.57 billion people in 2026, roughly 19% of the world. By 2100 the projection puts it near 3.81 billion, about 2.4 times its current size and around 37% of humanity. That gain of 2.24 billion is larger than the 1.92 billion the world nets over the same stretch. The reason those two numbers can point in different directions is that the world total is now a net of large gains against large losses: across the whole dataset, the countries that grow between 2026 and 2100 add about 3.13 billion between them, while the ones that shrink give back about 1.21 billion. Africa supplies roughly 72% of the additions. The regional totals sit side by side on our population by continent page.

This is the single largest redistribution of people in the projection, and it is worth being precise about what it is not. Africa is not projected to overtake Asia, which still holds about 4.62 billion in 2100. It is not a story about migration either. What it is, on this data, is arithmetic that has already happened: a very young population working its way forward.

None of it is migration

The easiest way to misread this projection is to imagine people arriving. Run the births and deaths forward from 2026 to 2100 and Africa’s natural increase alone comes to about 2.31 billion, which is more than the 2.24 billion the region actually gains. The difference, roughly 65.9 million, is net migration running the other way: on these assumptions Africa is a net sender of people for the rest of the century, and still grows by well over two billion.

Births are where you see it first. Africa already accounts for about 36% of the babies born worldwide in 2026, well ahead of its 19% share of people, at a cadence of one birth every 0.7 sec. By 2100 the projection has that at roughly 48% of world births. The crossing point is 2055: from that year on, more children are born in Africa than in Asia, even though Asia still holds far more people. Population totals lag births by decades, which is why the region’s share of the world only passes a third around 2081, long after its share of births does.

It is not Africa, it is about a dozen countries

The regional total hides how concentrated the growth is. Of Africa’s 2.24 billion gain, the five largest contributors supply about 48% and the ten largest about 65%. Ranked by people added between now and 2100 they run DR Congo, Nigeria, Ethiopia, Tanzania and Angola. DR Congo alone adds roughly 315 million, more than any other country on earth, which is why we track it closely on our DR Congo population page.

The split by sub-region is just as uneven. Middle Africa is projected to grow by a factor of about 3.5 times, while Southern Africa grows by only around 1.5 times. The seven countries and territories the UN groups as Northern Africa sit some way apart from the rest of the continent on both of the inputs that drive growth: a population-weighted fertility rate near 2.9 births per woman against about 4.3 across the other 51, and a median age of roughly 25 against 18. Those other 51 entries account for about 92% of the continent’s growth. Most of them also fill out the top of our fastest-growing countries list.

The number that matters is working-age people

Total population is the headline, but the more consequential figure is who is old enough to work. Summing the national age pyramids, Africa holds about 15% of the world’s people aged 20 to 64 in 2024, roughly 24% by 2050, and around 40% by 2100. In absolute terms that is a move from about 708 million to 2.20 billion working-age Africans.

Set that against the world. On the same basis the global working-age population grows by only about 6.4 million between 2050 and 2100, while Africa’s grows by roughly 870 million. After the middle of the century, essentially all net growth in the world’s working-age population comes from Africa, and the rest of the world in aggregate offsets it. Africa also already holds about 28% of everyone under twenty, which is the same fact one generation earlier.

What it does to the rankings

Growth rates are easy to skim past. Rank changes are not. Two African countries sit in the world’s ten most populous today. By 2100 the projection has four: Nigeria, DR Congo, Ethiopia and Tanzania. In the top twenty the count goes from 4 to 8.

The individual moves are large. Nigeria goes from 6th to 4th, passing the United States around 2057 on the way, a crossing we cover on the Nigeria overtakes the United States page. DR Congo moves from 15th to 5th, passing Japan as early as 2028. These are not close-run swaps at the margin. They are the consequence of one group of countries tripling while another contracts hard over the same stretch, and the full table is on our African century ranking.

Africa is slowing down too

Nothing here is a runaway. The projection has African fertility falling steeply: a population-weighted rate of about 4.1 births per woman today, roughly 2.7 by 2050 and around 2.0 by 2100, which is below the replacement level. By the end of the horizon 46 of the 58 African countries and territories in the dataset are modelled below 2.1 births per woman. The median age rises from about 20 to 36 over the same period.

Populations keep climbing anyway, because a population with a median age in the teens has decades of growth already built into its age structure: most of its future parents have been born. The effect is visible in the exceptions, where the same mechanism has already run further. Just two African entries have passed their maximum so far, and 15 in total peak before 2100. Among those of at least five million people the earliest are Tunisia around 2052, Morocco around 2058 and Libya around 2087, and the last to turn is Kenya, around 2098. Every country in that group already has a fertility rate below the African median of about 3.8, which is the mechanism in miniature: the places that turn first are the ones whose birth rates fell first.

What would change this

The direction is far more robust than the magnitudes. Africa’s young age structure is observed rather than assumed, so the fact of substantial growth is close to locked in for the next few decades. The 2100 figure is another matter entirely: it compounds fertility assumptions across three generations that are not yet born, and it is the most sensitive number on this page. A faster fertility decline than the medium variant assumes would pull the continental total down sharply without much changing the ordering; a slower one would push it up. Mortality assumptions matter less, and migration, on these numbers, barely registers against natural increase.

One definitional caveat: these are UN statistical regions, and Africa here means all 58 countries and territories in that grouping, including the Northern African ones whose demography differs sharply from the rest. The world itself is projected to peak around 2084 on this path, a turning point covered in When will world population peak? Africa is still growing at that point and for the rest of the horizon, which is the whole reason the peak arrives as late as it does.

All figures are the UN World Population Prospects 2024 medium variant, aggregated as described in our methodology. Projections are conditional statements about what follows from a set of assumptions rather than forecasts, and the century-end numbers on this page should be read as direction and scale rather than as detail.