Megacity growth is not evenly distributed. The regional picture looks different depending on whether you weigh it by count, density, or growth rate.
Home to the majority of the world's megacities, from the long-established metropolitan areas of Japan to the rapidly expanding urban regions of South and Southeast Asia. Tokyo, Delhi, Shanghai, Dhaka, and Mumbai all fall within this region.
The fastest-growing region by urban population percentage, though still home to fewer megacities than Asia. Cairo and Lagos anchor the continent's largest urban regions, with several other cities projected to cross the megacity threshold within a decade.
Urbanization here occurred earlier than in Africa or South Asia, producing large, relatively mature metropolitan areas such as São Paulo and Mexico City that have grown more slowly in recent years.
Fewer megacities by strict population count, but several metropolitan areas — including Moscow, Paris, and New York — remain among the world's most economically significant urban regions.