The population of Comoros in 2003 was estimated by the United Nations at 768,000, which placed it as number 154 in population among the 193 nations of the world. In that year approximately 5% of the population was over 65 years of age, with another 46% of the population under 15 years of age. There were 101 males for every 100 females in the country in 2003. According to the UN, the annual population growth rate for 2000–2005 is 2.83%, with the projected population for the year 2015 at 1,042,000. The government considers the country's high growth rate a major constraint to social and economic development. The population density in 2002 was 275 per sq km (713 per sq mi).
It was estimated by the Population Reference Bureau that 33% of the population lived in urban areas in 2001. The capital city, Moroni, had a population of 44,000 in that year. According to the United Nations, the urban population growth rate for 2000–2005 was 4.1%. Grande Comore, the largest island, has the largest populace, followed by Anjouan and then Mohéli.