UN World Population Prospects

World Population Prospects comes from the Population Division of the UN Department of Economic and Social Affairs (DESA), and is the UN's official series of population estimates and projections.¹ The 2024 revision is the twenty-eighth edition; the series has been prepared since 1951.^1,2 It was released on 11 July 2024, and a new revision comes every two or three years, the next due on 11 July 2027.² Only the latest revision is kept online in full; selected results from the 1992 to 2022 revisions are in an archive section of the download centre.²

The 2024 revision gives estimates for every year from 1950 to 2023 and projections from 2024 to 2100, for 237 countries or areas.^1,2 It draws on 1,910 national censuses held between 1950 and 2023, on vital registration (the official recording of births and deaths) and on 3,189 nationally representative surveys.¹ Since the 2022 revision, figures come in one-year steps of age and time, published both by single year of age and by five-year age groups.¹ Results are also added up for regions, World Bank income groups, Sustainable Development Goal regions and other groupings, such as economic and trading blocs.^1,2 Because official statistics have gaps, late counts and reporting errors, the UN's estimates for a country sometimes differ from that country's own figures.²

The main projection, the medium scenario, is probabilistic: thousands of possible future paths of births, deaths and migration are simulated and the medium scenario takes their mean or median.³ Prediction intervals of 80 and 95 per cent show how widely the paths spread.³ Thirteen further, deterministic scenarios vary the assumptions, for example fertility half a birth per woman higher or lower, constant fertility, zero international migration, or no births to girls under 18.³ Comparing them separates how much of future change comes from fertility, mortality, migration and the existing age structure.³ In the 2024 revision, world population is projected to peak at around 10.3 billion in the mid-2080s, up from 8.2 billion in 2024, with an 80 per cent likelihood that it peaks within this century.⁴

The main results are a series of Excel files of key indicators; the whole set can be downloaded as CSV for use in databases or statistical software.¹ An online Data Portal gives a subset of indicators with charts and an open API for programs.¹ The Summary of Results states that its figures and tables may be reproduced without permission under a Creative Commons licence, CC BY 3.0 IGO.⁴ Every UN entity uses these estimates for indicators that need a population figure.²

For someone modelling a place, the projections give the national and regional backdrop: how many people, of what ages, a country may have in each year to 2100, under a range of stated assumptions.^1,3 Each figure is for a whole country or area, or a group of countries.^1,2 For estimates of who lives inside an area smaller than a country, such as a district or a flood zone, WorldPop is the entry on this site that maps population onto a fine grid.