List of most populous nations by 2025
The United Nations Population Fund has calculated, based on current trends, the future population of the world's countries. These figures can easily change as events such as wars, diseases, or dramatic demographic changes would all greatly affect the results. The study projected the world population in 2025 to be 8.039 billion.
| Rank | Current Rank | Change | Country | Projected Population (millions) | Current Population (millions) |
| 1 | 1 | = | People's Republic of China | 1480.4 | 1294 |
| 2 | 2 | = | India | 1330.2 | 1049 |
| 3 | 3 | = | United States | 332.5 | 294 |
| 4 | 4 | = | Indonesia | 275.2 | 234 |
| 5 | 6 | +1 | Pakistan | 268.9 | 151 |
| 6 | 9 | +3 | Nigeria | 238.4 | 133 |
| 7 | 5 | -2 | Brazil | 216.6 | 182 |
| 8 | 8 | = | Bangladesh | 180.0 | 138 |
| 9 | 16 | +7 | Ethiopia | 136.3 | 67 |
| 10 | 7 | -3 | Russia | 131.4 | 145 |
| 11 | 11 | = | Mexico | 130.2 | 105 |
| 12 | 18 | +6 | Iran | 128.3 | 68 |
| 13 | 10 | -3 | Japan | 121.3 | 127 |
| 14 | 14 | = | Vietnam | 110.1 | 82 |
| 15 | 23 | +8 | Dem. Rep. of Congo | 105.9 | 57 |
| 16 | 12 | -4 | Philippines | 105.2 | 85 |
| 17 | 15 | -2 | Egypt | 95.8 | 75 |
| 18 | 17 | -1 | Turkey | 85.8 | 68 |
| 19 | 13 | -6 | Germany | 80.9 | 82 |
| 20 | 26 | +6 | South Africa | 71.6 | 43 |