South Korea’s fertility rate fell to roughly 0.75 births per woman in 2024, meaning a South Korean Generation Beta birth cohort could end up close to one-third the size of the generation that gave birth to it. That is an extreme case, but it illustrates a real question sitting underneath the marketing language around Generation Beta: in a growing number of countries, is this cohort actually shaping up to be the smallest generation on record, rather than simply the newest one?
What Would Make Generation Beta a Small Generation
“Smallest generation” needs a precise definition before it can be tested, because there are at least three different ways to measure it, and they do not always point the same direction.
Smallest absolute birth cohort. This compares the raw number of children born during Generation Beta’s 2025-2039 window against the raw number born during Generation Alpha’s 2010-2024 window, in a specific country.
Smallest share of total population. This compares Generation Beta’s percentage of a country’s population against the percentage that earlier generations represented at a similar life stage, which can shrink even where absolute numbers hold steady, if the older population is growing due to longer life expectancy.
Smallest relative to the preceding generation. This compares Generation Beta’s size against its own parents’ generation, roughly late Millennials and older Gen Z, which is the most direct way of capturing generational contraction, since it measures whether each generation is failing to replace the one before it.
By the third measure, in most low-fertility countries, Generation Beta is very likely to be smaller than the generation that produced it. By the first measure, in high-fertility countries, Generation Beta could be larger in absolute terms than Generation Alpha was, even as its share of an aging global population continues to shift.
The Global Fertility Decline Behind the Question
Global fertility has fallen from roughly 5 births per woman in the 1960s to about 2.2 in 2024, according to UN estimates, and more than half of the world’s countries and areas now sit below the 2.1 replacement threshold. That threshold matters because a country sustained below it, without offsetting immigration, will see each successive generation born smaller than the one before it, all else being equal.
The decline has not been uniform in speed. East Asian countries reached below-replacement fertility decades ago and have continued falling well past that threshold into what demographers call lowest-low fertility, generally defined as a total fertility rate at or below 1.3. European countries mostly fell below replacement more gradually and have stabilized at somewhat higher, though still sub-replacement, levels. Much of Sub-Saharan Africa remains well above replacement, though fertility there has also been declining, just from a much higher starting point and at a slower pace.
Countries Where Younger Birth Cohorts Are Already Shrinking
The clearest evidence for a shrinking Generation Beta comes from countries that have already spent a decade or more below replacement fertility.
| Country or Territory | Approx. Fertility Rate, 2024-2025 | Status |
|---|---|---|
| South Korea | approx. 0.75 | World’s lowest national fertility rate; below 1.0 since 2018 |
| Hong Kong | approx. 0.9-1.0 | Among the world’s lowest, alongside Macau |
| Macau | approx. 0.9 | Among the world’s lowest recorded rates |
| Taiwan | approx. 1.0 | Lowest-low fertility |
| Singapore | approx. 1.0-1.1 | Lowest-low fertility |
| Japan | approx. 1.2-1.3 | Sustained sub-replacement fertility for decades |
| China | approx. 1.0-1.3 | Below replacement since the early 1990s; births falling sharply |
| Italy | approx. 1.2-1.3 | Among the lowest in Europe |
| Spain | approx. 1.2 | Among the lowest in Europe |
South Korea’s own births roughly halved over the past two decades, and Statistics Korea has reported outright annual population decline in the country since 2021. China’s annual births have fallen sharply from their peak, a decline sharp enough that the country’s Generation Beta cohort could plausibly turn out to be meaningfully smaller in absolute terms than its Generation Alpha cohort, not just as a share of population.
Countries Where Generation Beta Could Still Be Large
The picture inverts almost completely once the lens shifts to Sub-Saharan Africa and parts of the Middle East and South Asia.
| Country | Approx. Fertility Rate, 2023-2024 | Note |
|---|---|---|
| Niger | approx. 6.2-6.9 | Consistently among the highest in the world |
| Somalia | approx. 6.1 | Among the highest globally |
| Chad | approx. 6.1 | Among the highest globally |
| Democratic Republic of the Congo | approx. 6.1 | Among the highest globally |
| Central African Republic | approx. 5.8 | Very high, slowly declining |
| Mali | approx. 5.6 | Very high, slowly declining |
| Nigeria | approx. 4.5-5.0 | High, driving one of the world’s largest birth cohorts |
The UN projects that nine countries, including Niger, Angola, and the Democratic Republic of the Congo, will see their total populations double between 2024 and 2054, a pace only possible with sustained high fertility across the Generation Beta years. In these countries, Generation Beta is not shrinking relative to Generation Alpha. If anything, given continued population momentum, it could be larger in absolute terms, even as its share of the national population may eventually decline as fertility gradually falls from very high levels.
Why Generation Size Can Change Even When Population Does Not
A national population total can stay flat, or even grow slightly, while its youngest generation still shrinks, because of two separate mechanisms. First, net immigration can offset a shrinking birth cohort without changing the underlying generational size born on that soil, meaning a country’s Generation Beta could be small by birth while its overall population, boosted by immigrants of all ages, holds steady. Second, an aging population living longer increases the number of older people relative to the number of newborns, shrinking a young generation’s percentage share of total population even where the absolute birth count barely moves.
This distinction matters for policy discussions that conflate “population decline” with “generational shrinkage.” A country can avoid outright population decline through immigration while still producing a historically small home-grown Generation Beta cohort, with very different implications for schools, pediatric healthcare capacity, and long-term workforce composition than a country experiencing both effects simultaneously.
What Smaller Generations Mean for Schools, Workers, and Families
The clearest, most immediate effect of a shrinking birth cohort shows up in schools. South Korea has already closed hundreds of elementary schools over the past decade due to insufficient enrollment, and similar patterns are emerging in parts of Japan, Italy, and China as smaller cohorts move through the education system. A meaningfully smaller Generation Beta in these countries would extend that trend through the 2030s and beyond, likely reducing the number of schools, pediatric medical practices, and children’s product markets these countries can economically sustain.
Further out, a small Generation Beta cohort becomes a smaller future workforce entering the labor market in the 2040s and 2050s, at precisely the moment these same countries will have very large elderly populations requiring support. This is the practical stake behind the “smallest generation” question. It is not a matter of demographic trivia but a leading indicator of the old-age dependency ratios these countries will face decades from now.
None of this is guaranteed to be negative in every respect. Some researchers argue that a smaller working-age generation, if paired with rising productivity and continued automation, could sustain living standards even with fewer total workers. That remains a contested, forward-looking claim rather than an established finding.
Could Generation Beta Reverse the Pattern
Fertility forecasts carry real uncertainty, and short-term reversals do happen. South Korea recorded ten consecutive months of rising births and marriages through early 2025, a modest but genuine uptick after years of continuous decline, though it remains far too early to call this a durable trend reversal rather than a temporary fluctuation, possibly tied to pandemic-delayed family formation finally catching up.
Government pronatalist spending has a mixed record. Hungary spent heavily on family incentives for over a decade and still recorded a record-low number of births in 2024, illustrating that financial incentives alone have not reliably reversed sustained sub-replacement fertility in the countries that have tried them most aggressively. Whether Generation Beta ultimately turns out smaller than Generation Alpha in any specific low-fertility country will depend on family formation decisions that have not yet been made, not on the demographic momentum already locked in from past birth cohorts.
Key Findings
- Global fertility fell from roughly 5 births per woman in the 1960s to about 2.2 in 2024, with more than half the world’s countries now below the 2.1 replacement threshold, setting up conditions for generational contraction in a large share of countries.
- South Korea’s fertility rate of approximately 0.75 in 2024 means its Generation Beta cohort could end up close to one-third the size of the generation that produced it, absent a significant and sustained reversal.
- China, Japan, Italy, Spain, and most of East Asia and Southern Europe show similar structural risk of a smaller Generation Beta relative to Generation Alpha, driven by sustained sub-replacement fertility.
- Nine countries, including Niger, Angola, and the Democratic Republic of the Congo, are projected by the UN to double their total populations between 2024 and 2054, implying their Generation Beta cohorts will likely be larger in absolute terms than their Generation Alpha cohorts.
- Immigration can mask generational shrinkage at the national population level, meaning “population decline” and “smallest generation” are related but distinct phenomena that should not be used interchangeably.
Conclusion
There is no single true answer to whether Generation Beta will be the smallest generation, because the answer depends entirely on which country and which measure are in question. In South Korea, Japan, China, and much of East Asia and Southern Europe, the structural conditions for a historically small Generation Beta cohort are already in place, locked in by fertility rates that have sat well below replacement for years.
In Niger, Somalia, and much of Sub-Saharan Africa, the opposite is true, with Generation Beta positioned to be larger in absolute terms than the generation before it. The honest framing is not “Generation Beta is shrinking” but “Generation Beta is diverging,” with the gap between its largest and smallest national cohorts wider than for any generation that came before it.
Frequently Asked Questions
1. Will Generation Beta be the smallest generation ever?
Globally, unlikely, since annual global births have remained relatively stable near 140 million and high-fertility countries continue contributing large absolute birth numbers. Within specific low-fertility countries such as South Korea, Japan, and China, however, Generation Beta could plausibly be the smallest generation on record.
2. Which countries have the most shrinking birth cohorts?
South Korea, Hong Kong, Macau, Taiwan, Singapore, Japan, China, Italy, and Spain all show sustained sub-replacement fertility that points toward a smaller Generation Beta than Generation Alpha in absolute or relative terms.
3. Does low fertility always mean population decline?
Not immediately. Population momentum from earlier, larger generations, along with net immigration, can keep total population stable or even rising for years after fertility falls below replacement. Eventually, sustained sub-replacement fertility does produce population decline once that momentum is exhausted.
4. Can immigration offset a smaller Generation Beta birth cohort?
Immigration can offset overall population decline, but it does not change the number of children actually born domestically. A country can maintain stable total population through immigration while still experiencing a historically small home-grown Generation Beta cohort.
5. Why is South Korea’s fertility rate so much lower than the global average?
Researchers point to a combination of factors, including high housing and education costs, demanding work culture, later average age at marriage, and changing social attitudes toward marriage and childbearing, alongside decades of policy intervention that has so far failed to reverse the trend.
6. Will Generation Beta be smaller than Generation Alpha worldwide?
It is close and uncertain. Both cohorts are projected in the range of 2 billion total births, and the outcome depends heavily on whether fertility in Sub-Saharan Africa and South Asia declines faster or slower than current UN projections assume.
7. What happens to schools when a generation shrinks?
Countries with sharply declining birth cohorts, such as South Korea and Japan, have already closed hundreds of schools due to insufficient enrollment, a trend likely to continue or accelerate if their Generation Beta cohorts remain smaller than previous generations.
8. Are any countries reversing their fertility decline?
South Korea recorded ten consecutive months of rising births and marriages through early 2025, a genuine but still preliminary sign of a possible partial rebound. It is too early to treat this as a confirmed long-term trend reversal.
9. Is a smaller generation always an economic problem?
Most economists view a rapidly shrinking working-age population as a fiscal and labor-market challenge, particularly for funding pensions and healthcare for a growing elderly population. Some researchers argue productivity gains and automation could offset part of this effect, though this remains a debated and unproven proposition.
10. Which measure should be used to define “smallest generation”?
There is no single correct measure. Absolute birth count, share of total population, and size relative to the preceding generation each capture a different aspect of generational contraction, and analyses should specify which one they are using rather than treating “smallest generation” as a single, self-evident statistic.
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
- Statistics Korea, annual fertility and birth data, 2022-2025
- World Bank, fertility rate data by country
- Al Jazeera, “S Korea breaks record for world’s lowest fertility rate, again,” 2023
