Projected Population 2100

The Democratic Republic of the Congo — a country most people cannot locate on a map without prompting — is projected to rank 5th in the world by population in 2100, with 431 million people. That would make it larger than today's United States, up from roughly 103 million today, and it is the single sharpest illustration of what the UN World Population Prospects 2024 data actually shows: the treemap of projected 2100 populations is almost unrecognizable from any map produced in the last hundred years.

Africa Will Hold More Than 1 in 3 People on Earth

Africa's total population is projected to reach 3.81 billion by 2100, up from roughly 1.45 billion today, raising the continent's share of global population from about 17% to 38%. Seven African nations will rank among the world's 15 most populous. Nigeria will reach 477 million, Ethiopia 367 million, and Tanzania 263 million — figures that would each rank among the world's top ten individually. Tanzania's nearly four-fold expansion, from 65 million today, vaults it into the global top 10 alongside countries that currently dwarf it economically.

The projections carry real uncertainty. The UN's own 2012 edition put Nigeria's 2100 population at 914 million — nearly double the 2024 projection of 477 million — a revision driven almost entirely by updated assumptions about when fertility rates would fall. Nigeria's fertility rate of roughly 5.1 children per woman today remains more than twice the global average of 2.3, and projections to 2100 require 80 years of compound assumptions about female education, urbanization, and economic development. The IHME, publishing in The Lancet, projects global population peaking earlier and lower — around 9.7 billion in 2064, declining to 8.8 billion by 2100 — compared with the UN's peak of 10.3 billion around 2084. The DRC's trajectory is particularly sensitive to climate risk: the Congo Basin faces water stress and conflict pressures that impose hard downside limits on population growth not fully captured in demographic models.

China's Collapse and the New Asian Hierarchy

China's projected population of 633 million by 2100 represents a loss of more than half its current 1.42 billion people, returning China to the population size it held in the late 1950s. Its current fertility rate of approximately 1.0 births per woman is among the lowest ever recorded for a large economy. The one-child policy (1980–2015) eliminated cohorts that would otherwise be today's parents, creating a self-reinforcing demographic spiral that cash incentives have so far failed to reverse.

The country that most disrupts the Asian hierarchy is Pakistan: 511 million by 2100, ranked third globally, just 24% behind China. Pakistan's fertility rate is not projected to fall below replacement level until around 2080, making it a demographic outlier among middle-income nations. By 2100, Pakistan, Nigeria, and the DRC will all sit between China and the United States in the global ranking — a configuration with no historical precedent. In 1950, the world's five most populous countries were China, India, the USSR, the United States, and Japan; by 2100, four of those five will be replaced by Pakistan, Nigeria, the DRC, and Ethiopia, none of which ranked in the global top 10 in 1950.

Europe and Japan: From Civilizational Weight to Demographic Margin

Europe held roughly 25% of world population in 1900 and around 22% in 1950. By 2100, Europe including Russia will account for just 5.8% of global population, with total numbers falling from about 750 million to 592 million. Eurostat projects the EU to shrink by 12% from current levels, with Italy facing a 40% decline — a loss of demographic scale that compounds existing fiscal pressures from aging populations dependent on narrowing working-age bases.

Japan's trajectory is the clearest leading indicator of where persistently low-fertility societies end up: from roughly 124 million today to 76.8 million by 2100, its lowest population since the 1940s. Japan has been losing people since 2010, the longest sustained demographic decline among major economies. South Korea, with the world's lowest recorded fertility rate of 0.75 births per woman — a figure Statistics Korea confirmed for 2023 — is projected to fall from 51.7 million to 21.8 million by 2100, a 57.8% decline. These trajectories do not describe slow erosion; they describe countries whose populations will roughly halve within a human lifetime.

Peak Humanity and the 2084 Inflection

World population is projected to peak at approximately 10.3 billion around 2084 — the first time in recorded history that global population will have peaked and then begun declining. The global median age will rise from 31 today to 42 by 2100, and the number of people over 65 will more than double to 2.4 billion. Brazil will shrink from roughly 215 million to 163 million, with South America's share of world population falling from around 5.4% to 3.7%. Oceania is the only non-African region where every major country still grows over the century: Australia is projected to reach 43 million, while Papua New Guinea nearly doubles to 18.6 million.

The speed of Africa's fertility transition will determine how closely these projections track reality — rapid urbanization and rising female education could pull actual 2100 African populations well below these figures, which would narrow but not reverse the structural shift already visible in current fertility differentials. The reordering of demographic weight embedded in today's birth rates is directionally unambiguous even if the exact magnitudes remain contested between the UN and IHME models.

For more data-driven analysis of global economics and the trends reshaping the world economy, visit econcoaching.com.