Human population projections

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Human population projections try to estimate how the number of people on Earth will change in the future. They help planning for food, water, health, and the environment. Projections depend on three main factors: how many babies are born (fertility), how long people live (mortality), and people moving between countries (migration). As these factors change, forecasts change too.

Global growth has slowed a lot. Population rose fastest in 1963, when the world grew about 2.3% each year. By 2023, that growth was down to about 0.9% per year, adding roughly 74 million people annually. Some scenarios even imagine population could start to shrink later this century.

The United Nations’ latest projection puts a peak in world population in the 2080s, at around 10.3 to 10.4 billion. After that, the population would slowly decline toward about 10.3 billion by 2100 under a middle-growth scenario. This shift mainly comes from birth rates falling faster in Africa and other regions.

Most future growth will come from less developed regions, especially Africa. Between 2020 and 2050, about 1.9 billion people are expected to be added worldwide, with about 1.2 billion of those in Africa. Africa’s share of the world population is projected to rise from about 17% in 2020 to around 38% by 2100, while Asia’s share falls from about 60% to roughly 45% by 2100. Nigeria is expected to grow a lot, potentially becoming one of the most populous countries, while China’s population is projected to decline.

Life expectancy is rising globally. For people born around 2000–2005, life expectancy was about 67 years; by 2095–2100 it could reach about 83 years in many places. Because there are many young people today, population growth can continue for several decades even as fertility falls—a phenomenon known as population momentum.

Migration also affects numbers, with people moving between regions influencing regional sizes and shares, though it’s not the main driver of global growth.

Urbanization is likely to increase the share of people living in large cities. In 2016, about 757 million people lived in the 101 largest cities; by the end of the century, a larger share of the population is expected to live in big urban areas.

Different groups model the future using different assumptions about fertility, mortality, and migration. The latest UN view is that the world’s population will keep growing into mid-century, peak in the 2080s, and then slowly decline toward 2100, with Africa and other less developed regions playing a major role in the near-term rise.