The demographics of Nauru, an island country in the Pacific Ocean, are known through national censuses, which have been analysed by various statistical bureaus since the 1920s.

The population density is 554 inhabitants per square kilometre (1,430 inhabitants/sq mi), and the overall life expectancy is 63.9 years.

The population rose steadily from the 1960s until 2006 when the Government of Nauru repatriated thousands of Tuvaluan and I-Kiribati workers from the country.

Nauru is inhabited mostly by Nauruans (92.1%), while minorities include those from Kiribati (2.4%), Fiji (2.2%), Australia (1.2%) and other (2.1%).

[1] The demographic history of Nauru is marked by several migrations: the area was first inhabited by Micronesian people about 3,000 years ago.

The next major population change was when Japanese occupied the island during World War II in 1942.

The most recent demographic switch was in the 2000s, when the government repatriated several groups of non-Nauruans from the country.

The proportion of the country's population aged 15 and over attaining academic degrees is one of the lowest in the world, reaching 7.9% in 2011.

Nauru has a universal health care system, and in 2012, an estimated 7.5% of its GDP was spent on healthcare.

The most significant sources of employment are phosphate mining, banking industries, and various coconut products.

The next demographic change came when Japanese occupied the island during World War II in the 1940s.

[9] The next major demographic change was in the 1960s; the country gained independence, and the percentage of Nauruans started to increase.

[10] The last major demographic change was in 2006 when the Government of Nauru repatriated almost all of the remaining Tuvaluan and I-Kiribati workers, following large scale reduction from the Republic of Nauru Phosphate Corporation (RONPhos) and government workers.

[21] If a cell is shaded light green and a dagger† stands beside a number, it indicates the estimate from The World Factbook.

There are a few active Christian missionary organisations, including representatives of Anglicanism, Methodism, and Catholicism.

The government has restricted the religious practices of the Church of Jesus Christ of Latter-day Saints and the Jehovah's Witnesses, most of whom are foreign workers employed by RONPhos.

[34] Literacy rate in Nauru, defined as "people who are currently enrolled in school and/or have reached at least grade 5 of primary education",[35] is 96.5%, as of 2011.

[36] The lone college, University of South Pacific, opened in the 1970s via distance courses, and in 1987 a campus was built on the island.

[45] Nauru's population has a life expectancy of 66 years at birth, ranking it 169th in the world.

[49] Compared to other countries that use the Australian dollar—Kiribati, Australia, and Tuvalu—Nauru ranks number one in terms of income.

The GDP is broken down into three categories: primary (18.7%—agriculture, hunting, forestry, fishing, mining, and quarrying), secondary (36.5%—manufacturing, electric, gas, water, and construction), and tertiary (44.8%—trade, hotel, restaurants, and various services) industries.

[52] A majority of the population are employed in phosphate mining, public administration, education, and transportation.

[55] During the 1990s, Nauru was famous for operating offshore banks, helping with money laundering.

[58] The owners of the trust purchased a fleet of ships and aircraft, a brewery in the Solomon Islands, hotels around the world, and real estate in Australia, the United States and Britain, which caused the trust to go bankrupt.