Rio de Janeiro is the capital of the state of the same name, Brazil's third most populous state, and the second most populous city in Brazil, after São Paulo. Listed by the GaWC as a beta global city, Rio de Janeiro is the sixth most populous city in the Americas. Part of the city has been designated as a World Heritage Site, named "Rio de Janeiro: Carioca Landscapes between the Mountain and the Sea", on 1 July 2012 as a Cultural Landscape.

Rio de Janeiro has the second largest municipal GDP in the country, and 30th-largest in the world in 2008. This is estimated at R$343 billion. In the city are the headquarters of Brazilian oil, mining, and telecommunications companies, including two of the country's major corporations, Petrobras and Vale, and Latin America's largest telemedia conglomerate, Grupo Globo. The home of many universities and institutes, it is the second-largest center of research and development in Brazil, accounting for 17 percent of national scientific output according to 2005 data. Despite the high perception of crime, the city actually has a lower incidence of crime than most state capitals in Brazil.