Roughly 140 million babies are born worldwide every year, according to United Nations medium-variant projections. Multiply that by the 15 years McCrindle Research assigns to Generation Beta, 2025 through 2039, and the arithmetic points toward a cohort of somewhere near 2 billion births. That number gets repeated often. It is rarely explained. This article walks through where it comes from, why it is not the same as “2 billion people alive in 2040,” and why the true size of Generation Beta will depend on decisions about fertility that have not yet been made in the countries that will supply most of its births.
How Large Could Generation Beta Be
Start with the baseline. The UN’s World Population Prospects 2024 revision estimates current global births at close to 140 million per year, a figure the medium-variant projection expects to hold fairly steady through the middle of this century before gradually declining toward roughly 126 million annual births by 2100 as fertility falls further in more countries. Applied across Generation Beta’s proposed 15-year span, that produces a raw estimate of approximately 2.0 to 2.1 billion births, broadly consistent with McCrindle’s own public projection that Generation Beta will represent about 16 percent of a global population expected to be somewhat larger than today’s 8.2 billion by 2035.
This is a back-of-envelope calculation, not an official UN cohort projection, because the UN does not publish population figures using generational names. Every number attributed to “Generation Beta” is a derived estimate, built by applying an informal 15-year birth-year definition to official age and birth data.
The Difference Between Cohort Size and Population Size
Three distinct numbers get blurred together whenever a generation’s “size” is discussed, and separating them is essential to using any of them correctly.
Total births
This is the raw count of babies born during the cohort’s window, roughly 2 billion for Generation Beta on current projections. It never changes once the window closes in 2039.
Surviving cohort at a future date
This is smaller than total births because of mortality, concentrated most heavily in infancy and early childhood in lower-income countries. Global under-5 mortality has fallen sharply over the past several decades, but it remains uneven, meaning the gap between “born” and “still alive five years later” is larger in some regions than others.
Population alive on a given date who happen to fall in that birth-year range
This is the number a business or policymaker usually actually wants, and it also incorporates net migration, since some Generation Beta children will move between countries as their families relocate.
| Concept | What It Measures | Approximate Value for Generation Beta |
|---|---|---|
| Total births, 2025-2039 | Raw birth count over the full window | approx. 2.0-2.1 billion |
| Surviving cohort, age 5 | Births minus early childhood mortality | approx. 1.9-2.0 billion (estimate) |
| Population by birth year, later census | Surviving cohort adjusted for migration | varies by country and year measured |
Global Birth Trends Behind the Estimate
The 140-million-a-year figure is not a static constant. It is the product of two forces moving in opposite directions: a still-large number of women of childbearing age worldwide, inherited from higher-fertility decades, and a fertility rate that keeps falling. Global fertility dropped from roughly 5 births per woman in the 1960s to about 2.2 in 2024, according to UN data, edging toward the 2.1 replacement threshold. More than half of the world’s countries and areas now sit below that threshold.
Despite falling fertility, annual births have not collapsed, because population momentum, the effect of having a very large number of women currently in their reproductive years even as each woman has fewer children on average, keeps total birth counts elevated for a time. The UN expects this momentum effect to keep global births close to current levels through roughly mid-century before a more visible decline sets in during the second half of Generation Beta’s span and beyond.
Where Future Generation Beta Births Will Occur
Generation Beta’s numerical center of gravity sits in a different place than most of the marketing conversation about the cohort. Sub-Saharan Africa and South Asia together are expected to account for roughly half of all Generation Beta births.
| Region | Approx. Share of Annual Global Births (2024-2025) | Approx. Regional Fertility Rate |
|---|---|---|
| Sub-Saharan Africa | approx. 29% | approx. 4.3 |
| South Asia | approx. 22% | approx. 2.2 |
| East Asia and Pacific | approx. 15% | approx. 1.4 |
| Latin America and Caribbean | approx. 8% | approx. 1.8 |
| Europe and Central Asia | approx. 7% | approx. 1.5 |
| Middle East and North Africa | approx. 8% | approx. 2.7 |
| North America | approx. 3% | approx. 1.6 |
This matters for the cohort-size question because Sub-Saharan Africa’s share of global births has been rising even as its own fertility rate slowly declines, since population momentum there is stronger than almost anywhere else. If Sub-Saharan African fertility falls faster than the UN’s medium variant assumes, over multiple decades, total Generation Beta births could land below current projections. If it falls more slowly, they could land above them. This single regional assumption does more to move the global Generation Beta total than any trend in North America, Europe, or East Asia, where birth counts are comparatively small and already declining.
How Migration and Mortality Affect Later Cohort Size
Birth counts and later population counts diverge for two structural reasons.
Mortality
Global under-5 mortality has fallen for decades, but it remains substantially higher in low-income countries, particularly across parts of Sub-Saharan Africa, than in high-income countries. Because Sub-Saharan Africa is expected to supply an increasing share of Generation Beta’s births, overall Beta mortality rates could pull the surviving cohort somewhat further below the raw birth count than was true for earlier generations born when high-income countries supplied a larger share of global births.
Migration
International migration reshuffles where Generation Beta children live without changing the global total. A child born in one country during the Beta years may spend a majority of their childhood in another country, particularly given ongoing migration flows toward North America, Europe, and Gulf states. This means “Generation Beta population by country” will always be a moving target, sensitive to migration policy in ways that global birth totals are not.
Generation Beta Within the 21st Century Population Story
Generation Beta’s births are occurring during a specific, identifiable phase of the global demographic transition. The UN’s World Population Prospects 2024 projects global population will rise from 8.2 billion in 2024 to approximately 10.3 billion in the mid-2080s before declining gradually to about 10.2 billion by 2100. Generation Beta’s youngest members, born in 2039, will be in their mid-40s when that peak arrives and will live through the early stages of the subsequent gradual decline.
As of 2024, population size had already peaked in 63 countries and areas, a group expected to shrink by roughly 14 percent over the following three decades. Another 48 countries are projected to peak between 2025 and 2054, a window that overlaps almost entirely with Generation Beta’s birth years. In the remaining 126 countries, population is expected to keep growing through at least 2054, with nine of them, including Niger, Angola, and the Democratic Republic of the Congo, projected to double in size over that period.
Generation Beta is therefore the first cohort whose birth years are split almost evenly across all three of these demographic categories: countries already shrinking, countries about to peak, and countries still expanding rapidly. No earlier named generation was born entirely within a world this demographically divided.
How Reliable Are Long-Range Cohort Projections
Any projection of Generation Beta’s eventual size rests on assumptions that extend a decade or more into the future, and the UN is explicit that uncertainty around global birth totals widens considerably the further out a projection reaches. In the UN’s own published sensitivity analysis, the range around medium-variant global birth projections widens to roughly plus or minus 9 percent by the early 2030s and considerably more by mid-century. Applied to a cohort still being born, that means a reasonable range for total Generation Beta births runs from perhaps 1.8 billion on the low end to 2.3 billion on the high end, rather than a single precise figure.
McCrindle’s specific claim that Generation Beta will reach 16 percent of global population by 2035 and 19 percent of the global workforce by that year should be read as a private research firm’s estimate built on top of these UN-style assumptions, not as an independently verified demographic finding. It is a reasonable order of magnitude, not a fixed fact.
Key Facts
| Metric | Figure | Year or Period |
|---|---|---|
| Approximate annual global births | 140 million | Current, UN medium-variant |
| Projected Generation Beta total births | approx. 2.0-2.1 billion | 2025-2039 |
| Global fertility rate | approx. 2.2 births/woman | 2024 |
| Sub-Saharan Africa and South Asia combined share of global births | approx. 51% | 2024-2025 |
| Countries with population already peaked | 63 | 2024 |
| Countries projected to peak 2025-2054 | 48 | UN WPP 2024 |
| McCrindle projected Beta share of global population | approx. 16% | 2035 |
| McCrindle projected Beta share of global workforce | approx. 19% | 2035 |
Conclusion
The widely repeated claim that Generation Beta will number close to 2 billion people rests on a defensible but uncertain calculation: roughly stable global birth rates multiplied across a 15-year window, adjusted downward for childhood mortality and complicated by migration. That number is more sensitive to fertility decisions in Sub-Saharan Africa and South Asia over the next decade than to anything happening in the wealthier countries where the Generation Beta label itself originated. Reporting the figure without that context turns a reasonable demographic estimate into something that sounds more precise, and more certain, than the underlying data actually supports.
Frequently Asked Questions
1. How many people will be in Generation Beta?
Based on current UN birth projections applied to the proposed 2025-2039 window, Generation Beta is likely to include roughly 2 billion total births, though the surviving population at any later date will be somewhat smaller due to childhood mortality, and its distribution across countries will shift due to migration.
2. Will Generation Beta be larger than Generation Alpha?
It is close to a toss-up based on current data. Generation Alpha is commonly cited at close to 2 billion births over its own roughly 15-year window. Because annual global births have stayed relatively steady, the two cohorts are likely to end up similar in size unless fertility declines faster or slower than currently projected in South Asia and Sub-Saharan Africa.
3. Where will most Generation Beta children be born?
Sub-Saharan Africa and South Asia together are projected to account for roughly half of all Generation Beta births, with Sub-Saharan Africa’s share rising over time as its fertility decline proceeds more slowly than in other regions.
4. Could fertility decline make Generation Beta smaller than expected?
Yes. If fertility in Sub-Saharan Africa or South Asia falls faster than the UN’s medium-variant projection assumes, total Beta births would land below the roughly 2 billion baseline estimate. The UN’s own uncertainty ranges around global birth projections widen considerably over multi-decade horizons.
5. Is the 2 billion figure an official UN estimate?
No. The UN does not publish population or birth statistics organized by generational name. The 2 billion figure is a derived estimate built by applying an informal 15-year cohort definition to official UN birth projections, and it should be treated as an approximation.
6. Why does mortality matter for cohort size?
Because a portion of any birth cohort does not survive to later childhood, particularly in regions with higher under-5 mortality. Since Sub-Saharan Africa is expected to supply a growing share of Generation Beta’s births, this effect is likely to be somewhat more pronounced for Beta than it was for generations born when wealthier, lower-mortality countries supplied more of the world’s births.
7. How does migration change Generation Beta’s population by country?
Migration redistributes where Generation Beta children live over their lifetimes without affecting the global total, meaning country-level Generation Beta population figures will keep shifting for decades after the cohort finishes being born in 2039.
8. What does McCrindle’s 19 percent workforce estimate mean?
It is a projection that by 2035, people born within Generation Beta’s proposed window will make up about 19 percent of the global workforce, primarily reflecting the oldest members of the cohort entering their first jobs, alongside the arithmetic of overall workforce size. It is a private-sector estimate rather than an official labor statistic.
9. How does Generation Beta fit into the UN’s population peak projections?
Generation Beta is being born as the global population continues rising toward its projected peak of about 10.3 billion in the mid-2080s. Its members will be entering middle age around the time that peak arrives and will live through at least the early years of the gradual global decline projected to follow.
10. Why do projections about Generation Beta carry more uncertainty than projections about Generation X or Millennials?
Because Generation Beta’s birth years have not fully elapsed. Cohorts like Generation X or Millennials can be measured using completed birth and mortality data, while Generation Beta’s final size depends on choices about fertility, particularly in high-birth-count regions, that have not yet been made or observed.
Sources
- United Nations, Department of Economic and Social Affairs, Population Division, “World Population Prospects 2024: Summary of Results,” July 2024
- United Nations, World Fertility 2024 report, Population Division
- United Nations Population Facts 2019/6, global annual births estimate and prediction interval methodology
- McCrindle Research, Generation Beta public projections, 2024-2025
- World Bank, fertility rate and under-5 mortality data by region
