Subscribe
The world's population is projected to peak within this century, with a current probability of 80 per cent, up from 30 per cent a decade ago, according to the World Population Prospects 2024 report by the United Nations. This shift is driven by substantial declines in fertility rates across highly populated countries, presenting a crucial pivot point for global sustainability and policy adaptation.
Currently at 8.2 billion, the total number of people is expected to soar to around 10.3 billion by the mid-2080s, marking a milestone in human history. Following this peak, a gradual decline is projected, settling at 10.2 billion by the century's end, the UN estimated.
"The size of the world’s population in 2100 is now expected to be six per cent lower — or 700 million fewer — than anticipated a decade ago," the authors of the report noted.
One in four people worldwide resides in countries where populations have already reached their zenith, the authors highlighted. In 63 nations, encompassing 28 per cent of the global populace, populations peaked before 2024. In another 48 countries, housing 10 per cent of the world's inhabitants, populations are anticipated to crest between 2025 and 2054.
The remaining 126, including India, are expected to witness continued growth into mid-century or beyond. In fact, India has been estimated to be the most populous country throughout the century.
The early peaking of the global population and the estimation of a lower total population by the end of the century represent significant shifts in demographic trends, driven by a combination of factors related to fertility rates, mortality rates, and migration patterns.
One of the primary reasons for the earlier-than-anticipated peak in global population is the widespread decline in fertility rates. Across the globe, more countries are experiencing lower birth rates. The findings of the analysis showed that women now are giving birth to 2.3 babies on an average, down from 3.3 in 1990. Over half of all countries now experience fertility rates below 2.1 births per woman, the threshold required for population maintenance without migration.
Increased access to education, particularly for women, and the widespread availability of contraceptives have empowered individuals to make informed decisions about family planning, the authors highlighted. Additionally, urbanisation and changes in societal norms regarding family size have contributed to a decrease in the number of children per family, they added.
In many developing countries, fertility rates have dropped significantly as economic development progressed and healthcare systems improved. These countries are moving through the stages of demographic transition faster than previously expected, shifting from high birth and death rates to lower rates. This transition results in a temporary population boom followed by stabilisation and, eventually, a decline, the authors explained.
However, concerns persist around early childbearing, impacting 4.7 million births annually to mothers under 18, with 340,000 occurring to girls under 15, the report flagged. Addressing this issue through enhanced education and delaying marriage and childbirth could significantly bolster women's health and participation in society, according to UN.
Improvements in healthcare and living conditions have also played a role in shaping population trends. Enhanced medical technologies and better access to healthcare services have led to a decline in mortality rates, particularly infant and child mortality.
Post-COVID-19, global life expectancy has rebounded, the report showed, reaching 73.3 years in 2024 — an increase of 8.4 years since 1995 — with projections suggesting a rise to 77.4 years by 2054.
This longevity improvement is expected to be underpinned by a youthful demographic structure, the authors observed. Past growth momentum will be the primary driver of global population increases through the mid-century, they stressed.
The number of women aged 15-49 (reproductive age) is projected to rise from nearly two billion in 2024 to around 2.2 billion by the late 2050s, sustaining growth even if fertility rates drop to replacement levels. This youthful age structure, a product of past growth, will account for 79 per cent of the population increase through 2054, adding about 1.4 billion people.
But as life expectancy increases, the age structure of the population changes, leading to an ageing population in many parts of the world, the experts underlined. While this has contributed to population growth in the short term, the long-term effect is a decrease in the natural population increase as the proportion of elderly individuals grows and the number of births continues to decline.
Additionally, despite overall improvements in child mortality, high levels of child mortality persist in many regions, particularly in countries with high fertility rates such as the Democratic Republic of the Congo, India, Nigeria and Pakistan.
Economically, countries with youthful populations and declining fertility face a critical window for harnessing demographic dividends through strategic investments in education, health, and infrastructure. However, the looming demographic shift towards an older population — expected to outnumber children by the late 2070s — calls for proactive measures in workforce adaptation and lifelong learning.
By the mid-2030s, those aged 80 and above will outnumber infants, reaching 265 million. Countries experiencing advanced demographic ageing should leverage technology to boost productivity across all age groups, promote lifelong learning and retraining, support multigenerational workforces, and create opportunities for older individuals to continue working.
Ageing populations also place increased demand on healthcare and social protection systems. The need for long-term care, chronic disease management, and end-of-life care will rise, requiring substantial investments in healthcare infrastructure and services. In countries like Nigeria, the share of persons aged 65 or older is projected to increase from 5 per cent in 2054 to 12 per cent in 2100 . This demographic shift underscores the importance of developing comprehensive health and social protection systems that can accommodate the growing needs of an ageing population, according to the authors of the report.
Migration emerged as a pivotal factor in shaping future populations, with immigration expected to counterbalance declining fertility rates in some 50 countries. Conversely, in 14 countries with ultra-low fertility, emigration may reduce population sizes through 2054.
Gender equality will be a crucial lever in managing population dynamics, offering pathways to mitigate rapid growth or decline. The analysts advocated for policies promoting women's empowerment, including access to reproductive health services and equitable caregiving responsibilities, for fostering sustainable demographic transitions.
Although India has crossed the replacement fertility rate, its population will keep growing until the mid-2060s due to population momentum, according to Nandlal Mishra, senior research fellow, International Institute for Population Sciences, Mumbai. “At this stage, population control policies are unnecessary and may even have adverse effects. Instead, we should focus on investing in education, health, and infrastructure, and implement reforms to create jobs and enhance government efficiency,” he shared.
Moreover, India will benefit from its demographic dividend until the 2050s, with more than 60 per cent of the population in the working-age group, the expert highlighted. “To capitalise on this opportunity, it is crucial to invest in education, health, and infrastructure, and to implement reforms that create jobs and improve government efficiency.”
But early childbearing remains a pressing issue, with serious implications for the country’s young women and their children. “According to the NFHS-5 (2019-21) data, the adolescent fertility rate is 43 per 1,000 women aged 15-19, down from 51 in NFHS-4 (2015-16). Despite remarkable decline in child marriage, about one in five girls in the country is still married before the age of 18, which is a major contributor to early pregnancies and high-risk births,” Mishra highlighted.
Addressing this issue through educational investments and delaying marriage and first childbirth, the analysts wrote, could greatly improve women's health, educational outcomes and workforce participation in India.