This article is a list of countries by military expenditure, the amount spent by a nation on its military in a given year. Military expenditure figures are presented in US$ based on either constant or current exchange rates. These results can vary greatly from one year to another based on fluctuations in the exchange rates of each country's currency. Such fluctuations may change a country's ranking from one year to the next.
The first list is based on the Stockholm International Peace Research Institute (SIPRI) Yearbook 2014 which includes a list on the world's top 15 military spenders in 2013, based on current market exchange rates. The second list is based on the 2014 edition of "The Military Balance" published by the International Institute for Strategic Studies (IISS) using average market exchange rates. The third and last list is based on the SIPRI military expenditure database for the year 2012, again based on current market exchange rates.