Statistics · checked October 2026
Global Fertility Decline Statistics (2026)
How fast fertility is falling, where, and what it means for cohort sizes.
More than half of all countries are now below the replacement fertility level of 2.1, and South Korea's 0.72 is the lowest national fertility rate ever recorded anywhere.
| Statistic | Figure | Year | Source |
|---|---|---|---|
| Replacement level | 2.1 children per woman | 2026 | Demographic standard |
| World average fertility | ~2.2 | 2026 | UN WPP |
| Countries below replacement | More than half | 2026 | UN WPP |
| Lowest ever recorded (South Korea) | 0.72 | 2024 | Statistics Korea |
| China | 1.0 | 2026 | UN WPP |
| Highest profiled (DR Congo) | 6.0 | 2026 | UN WPP |
| Iran, 1980s to today | Over 6.0 to 1.7 | 1980–2026 | UN WPP |
| Colombia, one decade | 2.4 to 1.6 | 2015–2025 | UN WPP |
| Fastest projected child-population fall | South Korea, −38% by 2040 | 2040 projection | UN WPP |
| Countries holding child population flat through migration | Australia, Canada | 2026 | UN WPP |
Faster than projected
The pattern of the past decade is that fertility has fallen faster than projections assumed, in country after country. Iran fell from above 6 to below 2 in about thirty years; Colombia fell from 2.4 to 1.6 in roughly ten.
That matters for every projection on this site: if anything, the declines shown in our 2040 figures are understated rather than overstated.
What it does not mean
Falling below 2.1 does not shrink a population immediately. Population momentum keeps it growing for a generation or more.
Frequently asked
What is the lowest fertility rate in the world?
South Korea, at 0.72 children per woman — the lowest ever recorded for any country.
How many countries are below replacement?
More than half of all countries are now below the 2.1 replacement level.
Does low fertility mean the population falls immediately?
No. Population momentum means a country with many people of childbearing age keeps growing for years after fertility drops below replacement.
AlphaBetaMinds (2026). Global Fertility Decline Statistics. Retrieved from https://alphabetaminds.com/statistics/fertility-decline-statistics