Sydney — UN urban centre
Sydney: 4,150,917 people. Reference: 2025 annual estimate · World rank #107 of 12,138 source urban centres. Source: UN DESA, World Urbanization Prospects 2025 (CC BY 3.0 IGO). Source identifier: 2139; territory: Australia (AUS). UN source workbook.
Method: Degree of Urbanisation (contiguous 1 km2 cells, density 1,500+ people/km2, total 50,000+). This is a source-defined urban centre, not a municipality or province. No association with a separate administrative entity is inferred from proximity or name.
Source centroid: -33.859, 151.079. National context uses World Bank estimates, a separate series and geography; no national share is inferred here.
UN population series
| Year | People | Method |
|---|---|---|
| 1975 | 2,221,676 | Estimate |
| 1980 | 2,347,920 | Estimate |
| 1985 | 2,536,158 | Estimate |
| 1990 | 2,715,328 | Estimate |
| 1995 | 2,881,012 | Estimate |
| 2000 | 2,858,429 | Estimate |
| 2005 | 2,973,683 | Estimate |
| 2010 | 3,321,179 | Estimate |
| 2015 | 3,678,440 | Estimate |
| 2020 | 4,067,000 | Estimate |
| 2025 | 4,150,917 | Estimate |
| 2030 | 4,272,146 | Projection |
| 2035 | 4,340,983 | Projection |
| 2040 | 4,402,339 | Projection |
| 2045 | 4,471,506 | Projection |
| 2050 | 4,554,766 | Projection |
Largest UN urban centres · Fastest-growing urban centres
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