Human population projections

Human population projections are attempts to show how human populations might change in the future. These projections are an important input to forecasts of the population's impact on the planet and humanity's future well-being. Models of population growth take trends in human development and apply projections into the future. These models use trend-based-assumptions about how populations will respond to economic, social and technological forces to understand how they will affect fertility and mortality, and thus population growth.

The 2022 projections from the United Nations Population Division (UN) (chart #1) show that annual world population growth peaked at 2.2% per year in 1964, has since dropped to 0.9% in 2023, equivalent to about 74 million people each year, and could drop even further to minus 0.1% by 2100. Based on this, the UN projected that the world population, 8 billion as of 2023, would peak around the year 2084 at about 10.3 billion, and then start a slow decline, assuming a continuing decrease in the global average fertility rate from 2.5 births per woman during the 2015–2020 period to 1.8 by the year 2100 (the medium-variant projection).

However, estimates outside of the United Nations have put forward alternative models based on additional downward pressure on fertility (such as successful implementation of education and family planning goals in the United Nations' Sustainable Development Goals) which could result in peak population during the 2060–2070 period rather than later.

According to the UN, all of the predicted growth in world population between 2020 and 2050 will come from less developed countries and more than half will come from sub-Saharan Africa. Half of the growth will come from just eight countries, five of which are in Africa. The UN predicts that the population of sub-Saharan Africa will double by 2050.