What India Becoming the World's Most Populous Country Means

Continued population growth in India and depopulation in China mean that India is now assuming the throne as the world’s most populous country. From population size alone, not much can be inferred about India’s future, but a deeper dive into its demographic dynamics shows that the country’s leaders need to move quickly to make the most of their favorable age structure and maximize the country’s opportunity for accelerated economic growth.

Today, India’s population of 1.428 billion is nearly four times larger than the 361 million counted just after Partition in the 1951 census. That’s the India most people know, the “population bomb” biologist Paul Ehrlich described in his famous (and problematic) tome about overpopulation after he visited India in the mid-1960s. Despite its overall growth, India’s population dynamics today are little like those Ehrlich described. The average number of children per woman was nearly 6 in the 1960s, but today the average is only 2, which is considered below replacement level (UN demographers put India’s replacement level at 2.19). That average masks some internal differences, but only five Indian states have a fertility rate above 2, and the highest is Bihar at just under 3. 

India’s rapid fertility decline is emblematic of the global trend. As of 2022, half of the world's countries had below-replacement fertility rates; in 2000, just over one-third did.

India’s population will keep growing, but its age composition is shifting.

Decades of below-replacement fertility will set any country on the path toward shrinking, barring a large volume of immigration. China’s population has already begun to shrink but even with low fertility, India’s population grows by one million each month and it will be after mid-century before India begins to depopulate. That is because much of India’s growth is baked in from the past and driven by “population momentum,” which is the tendency of a population to keep growing even if fertility falls because the size of childbearing cohorts is relatively larger from when fertility was higher (more potential mothers). In fact, India’s population is so large that it will drive much of the expected increase in global population between now and mid-century. When the world hits 9 billion sometime around 2037, 1.6 billion people will be Indian.

But the age structure of India’s population is drastically changing. The India of 25 years from now is fairly certain. India’s median age will be about 33–34 years, up from 28 years today and 21 years in 1998. That’s an increase of 12 years over a 50-year timespan, and just a shade behind increases in the global median age. The people who will give birth between now and 2048 are already born and there is a good sense of their reproductive tendencies (Indian women say they want about 1.6 children on average, so fertility will likely continue to trend downward). Given the size of those childbearing cohorts, plus modest life expectancy increases so that there will be more older people in India, India’s population will add only 230 million over the next 25 years. This is significant, but India has added 430 million over the last 25 years, from a population of 1 billion in 1997. As we see from the following figures, India’s age structure is becoming “stovepiped” when viewed from a 50-year time span, similar to the age structure of world population as a whole. India will stay relatively young for a while, but the number of young people aging into India’s workforce peaked a few years ago. This may make future job creation easier.

Remote Visualization

India’s demographic dividend is not guaranteed.

With that demographic profile, India has the conditions to reap a demographic dividend—a boost in economic growth from higher proportions of people of working age—if the right government policies are in place, such as investments in human capital. As in China, India’s leaders saw slower population growth as a prerequisite for economic development. Unlike China, however, India has not made the same investments in human capital in order to achieve those goals. Literacy, particularly for women, and education trail and the country needs to step up investments in health, as shown by its high infant mortality rate. Altogether, this means India needs to make serious investments if it is to maximize a demographic dividend.

And India needs to hurry. Western states saw fertility decline because of economic development; India’s declines came from family planning programs. That means the pace of demographic change has been faster, and the window of opportunity in which India has to reap its demographic dividend is shorter. It will have taken 75 years for the 60-plus population to grow from 15 percent to 30 percent in Western Europe. The same shift will take India only 34 years.

India is still relatively rural, although Indian cities are steadily growing. Delhi has been one of the world’s fastest growing cities, but on the whole India’s urbanization has lagged compared to what is expected given India’s global prominence. The United Nations places India’s urbanization at only 33 percent—China’s urbanization, in contrast, is 65 percent. Urbanization has historically been a key indicator of economic potential because it concentrates services, ideas, and jobs, so India’s low urbanization places a ceiling on their economic growth. Using recent urban data, one spatial modeling study projected five key Indian cities to grow an average of 1.5 to 2 times in the next decade. India’s National Commission on Population expects to reach over 38 percent by the middle of next decade, but that is still quite low. So, India has high urban growth potential, but is far behind the curve.

There are really two Indias.

Due to differences in fertility rates and emigration rates between the north and south, India is both a young country and an aging one, a microcosm of the global demographic divide. India’s northern states struggle more with poor health and illiteracy, while in the south, Kerala is already finding it difficult to staff assisted living homes for the elderly. It is tough to set policy priorities when the county has to address two very different population issues at the same time.

There is also the India for men and the India for women. According to the World Bank, just 23 percent of Indian women perform paid work, compared with 37 percent in Bangladesh and 63 percent of women in China. In India, much of this work is in the informal economy, which puts women at greater risk for financial insecurity in old age. Indian women enroll in higher education at higher rates than Indian men but India’s economy remains male-dominated. For India to maximize economic growth, they need better alignment between skills and jobs.

Population dynamics will be central for India’s future.

India’s population dynamics lay the groundwork for its future, but there is no guarantee that slower growth and a higher median age will translate to strong economic growth. Likewise, there is no guarantee that slower growth will lead to a cleaner, more sustainable environment. If all goes as planned, the 1.4 billion and counting people in India will see rising standards of living over the coming decades. That means affordable and realistic options for consumption in India are imperative, and India can model this greener path for the younger and dynamic economies in Africa, like Ethiopia’s, which will be following them on this demographic path. Environmental goals can support economic goals, too, if they include investments in green labor markets and industries.

Jennifer D. Sciubba is senior associate (non-resident) with the Project on Fragility and Mobility at the Center for Strategic and International Studies in Washington, D.C., and a Scholar at the Wilson Center. She is the author of 8 Billion and Counting: How Sex, Death, and Migration Shape Our World.