Delhi's 2021 population is now estimated at 31,181,376 . In 1950, the population of Delhi was 1,369,369 . Delhi has grown by 890,440 since 2015, which represents a 2.94% annual change. These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Delhi, which typically includes Delhi's population in addition to adjacent suburban areas.
Delhi, or the National Capital Territory (NCT) of India, is a large metropolitan area in India. Delhi is the fifth most populous city in the world and the largest city in India area-wise. Delhi has an estimated 2016 population of 18.6 million.
The NCT and its urban area are granted the special status of National Capital Region, and this NCR includes neighboring cities of Baghpat, Alwar, Sonepat, Gurgaon, Ghaziabad, Faridabad, Greater Noida, Noida, and nearby towns. The NCR has an estimated population of 24 million, exceeding the Delhi population of 17.8 million in 2014.
Delhi has a rapidly growing population, which was near 16.7 million in 2011.
Delhi covers a large area, totaling around 1,484 square kilometers. The city has a population density of 29,259.12 people per square mile, which is one of the highest in the world.
The largest ethnic group is Indo-Aryan (72%), followed by Dravidian (25%), then Mongoloid and other groups (3%), as of 2000. Delhi has a skewed female-to-male ratio, with 866 women for every 1,000 men. The city has a literacy rate of 86% (91% for men and 81% for women). Hindi is the most commonly spoken language (81%), followed by Punjabi (7%) and Urdu (6%). Nearly 82% of the population practices Hinduism, while 12.86% practices Islam. Christianity accounts for 0.87% of the population, while Buddhism accounts for just 0.11%.
Delhi has been continuously inhabited since at least the 6th century, and it has been the capital of many empires and kingdoms over its history. It has also been captured, destroyed and rebuilt numerous times. It was the site of Indraprastha, the mythical capital of the Pandavas, and it became a major trade route between the Gangetic plain and northwest India during the time of the Delhi sultans. In 1639, the walled city of Shahjahanabad was built in Delhi to serve as the capital of the Mughal Empire until 1857. Today, Shahjahanabad is in Old Delhi.
In 1911, the British decided to change the capital of India to Delhi from Calcutta, and New Delhi was built in 1912 south of the old city. Today, New Delhi is part of the larger city of Delhi, and New Delhi is the capital of India.
Delhi is one of the fastest growing cities in the world, reaching over 18 million this year from just 400,000 in 1901. In 2001 alone, its population increased by 215,000 due to natural growth and 285,000 through migration. By 2020, Delhi is expected to be the third largest conurbation after Tokyo and Mumbai.
Delhi struggles with its rapid growth and is facing substantial pressure to improve commercial and residential infrastructure.