Being the second most populated city in India, Delhi is a national capital and also the biggest trading center and largest source for small industries in North India. Due to this fact many migrants from neighboring states and other parts of the country are drawn towards Delhi. The report of 2011 census states that the population of Delhi is 16,753,235. It is also added that 11,297 persons per km2 is the density population along with a sex ratio of 866 women per 1000 men, with 86.34% literacy rate. The birth, death rate and infant mortality rate during the year 2004 per 1000 population was about 20.03, 5.59 and 13.08 respectively. There was an enhancement in population in the year 2001, by 285,000 which was an effect due to migration. 215,000 was another enhancement due to natural population growth. This stands to be the key reason for the fast growth of Delhi. By 2015, Delhi is anticipated to be the largest urban sprawl in the world after Tokyo and Mumbai. The Dwaraka sub city which is a residential area in Delhi is projected to come up quickly within the city.

Nearly 81% of Delhi population confers to Hinduism and is the major religion followed. The other religions are Muslims (11.7%), Baha’i (0.1%), Sikhs (5%), Christians (0.94%), and Jains (1.1%). Buddhism, Judaism and Zoroastrianism are other minor religions present here. Being Hindustani, Hindi is the major language spoken and written here with ample Punjabi and Urdu speaking people. These two languages also hold second language category in the city.
The estimate of 1999-2000 states that population living below poverty line which means people living below US$11 and less per month in Delhi would be about 1, 149,000. Another calculation states that it is about 8.23% of the total population when equated with 27.5% population of India as whole. Reports also state that nearly 52% of Delhi residents dwell in slums without proper facilities such as water, electricity, sewage, sanitation and proper housing facility. The highest percentage of crime rate is 16.2%, as submitted by record in the year 2005 amongst the other Indian cities. The kidnapping and abduction cases are recorded as 9.3% where the national rate is 2.2%. Delhi also ranks for 15.4% of crime rate amongst women.

Density of Delhi

The population density of Delhi is the highest with 6352 persons per sq. km when a comparison is made with other states and Union territories by 1991 census. According to the density of population Delhi is fifth amongst main cities like Mumbai, Calcutta, Bangalore, Hyderabad and Chennai. The ninth five year plan (2002) came up with a result that density of population of Delhi would be 10,062 per sq.km compared with an envisioned rate of 313 per sq.km.

Sex Ratio

The sex ratio which shows the number of females for thousand males has slumped from onwards 1941. The census of 1991 states that sex ratio of 827 is lower than the ratio of 927.

Literacy Rate

Reports show that the literacy rate was 14% in the year 1931and enhanced to 75% in 1991. This rate is advanced than the national literacy rate of 52% of 1991.  The 1991 census reports states that male literacy rate was 82% where females was 67%. The census report of 1991 also opens up that Delhi ranks sixth with regards to literacy. The NSSO or National Sample Survey Organization, during their 53rd round of Socio-economic Survey brought out that the literacy levels of Delhi was 85% in 1997 when compared to the 62% of national literacy levels. The same survey also states that the male and female literacy rate during 1997 were 91% and 76% when compared with the national literacy rates of 73% and 50% for males and females respectively.

Family Size

The 1991 census states that the family size was an average of 5.06 persons. The percentage calculation for family members states that 50% of families hold members 3-5 persons and 9% with 9 and more persons. The urban areas have a family size of 4.99 persons when equated with the rural families of 5.90 persons.

Vital Rates

The Civil registration system has come up that the birth and death rates have dropped since 1991. During 1991 census, the birth rate was 28.52 per 1000 which dropped to 24.56 per 1000 in 1997. The death rate is another factor which was 6.35 per 1000 in the year 1991and dropped to 6.05 per 1000 in 1997. The record of birth and death rate had an effect of Delhi population which also dropped from 2.21% in 1991 to 1.85% in 1997. In 1992 the infant mortality rate was 32.96 per 1000 live births and dropped to 25.95 in 1997.

Migration

The approximate migration is based on the birth and death rates and increase in population. Reports also states that the migration has been elevating since 1991 and at present is more than one and a half of the population (1:1.5.5) in 1997. In 1991, the natural increase in population was about 2.11 lakh when equated with the migration of 1.78 lakh. But in 1997 the natural increase has been reached to 2.18 lakh whereas as migration was calculated as 3.37 lakh.

Rural-Urban Ratio

In 1901, the rural population of Delhi was 47.24% which gradually dropped to 7.27% during the year 1981, but enhanced to 10.07% in 1991. This reverse trend of rural population during 1981-1991 was because of the eruption of unauthorized colonies in rural areas.