There are three lists of countries of the world sorted by their gross domestic product (GDP) (the value of all final goods and services produced within a nation in a given year). The GDP dollar estimates given on this page are derived from purchasing power parity (PPP) calculations.

Using a PPP basis is arguably more useful when comparing generalized differences in living standards on the whole between nations because PPP takes into account the relative cost of living and the inflation rates of the countries, rather than using just exchange rates which may distort the real differences in income. However, economies do self-adjust to currency changes over time, and technology intensive and luxury goods, raw materials and energy prices are mostly unaffected by difference in currency (the latter more by subsidies), despite being critical to national development, therefore, the sales of foreign apparel or gasoline per liter in China is more accurately measured by the nominal figure, but everyday food and haircuts by PPP.

Several economies which are not considered to be countries (world, EU, and some dependent territories) are included in the list because they appear in the sources. These economies are not ranked in the charts here, but are listed in sequence by GDP for comparison.

• The first table includes data for the year 2008 for 179 of the current 185 International Monetary Fund members and the Republic of China (Taiwan), as well as for the following unranked entities: the European Union, China's Hong Kong Special Administrative Region, and the world. Data are in millions of international dollars and were calculated by the International Monetary Fund. Figures were published in April 2009.
• The second table includes data for the year 2008 for 178 of the 193 currently recognized sovereign nations, the two Chinese Special Administrative Regions (Hong Kong and Macau), and for the unranked entities of the world and the Eurozone. Data are in millions of international dollars (rounded to the nearest 100 million) and were compiled by the World Bank. Figures were published in July 2009.
• The third table is a tabulation of the CIA World Factbook GDP PPP data update of 2009. The data for GDP at purchasing power parity (PPP) have also been rebased using the new International Comparison Program (ICP) price surveys and extrapolated to 2007. Final figures are estimates in millions of international dollars.