India's population has increased to some 1.21 billion people, or 17 per cent of the world’s population, according to the country’s latest census.
The increase of 181 million over the last decade is close to what officials had estimated.
While it is a 17.6 per cent increase from the 2001 census, it is slower than the previous count that showed 21.5 per cent growth.
The number of people living in India now is almost equal to the combined population of United States, Indonesia, Brazil, Pakistan, Bangladesh and Japan.
The census indicated a continuing preference for male children over females in a country where female infanticide is still common and the government has banned hospitals from revealing the sex of unborn children to their families.
A gender breakdown showed 914 girls for every 1,000 boys under the age of six, compared with 927 for every 1,000 in the last census.
"This is a matter of grave concern," Census Commissioner C. Chandramauli said.
The literacy rate went up to 74 per cent nationwide for people aged seven and older, from about 65 per cent in the last census.
Officials said it would require up to a year of data analysis before official numbers could be released.
The count is conducted every 10 years but faces big challenges given India's vast size and diversity of cultures.
PA