FDI

FDI can be

Finance
 Federal Deposit Insurance Corporation, a United States government corporation
 Foreign direct investment, purchase of an asset in a country by another country's company
 fDi magazine, a British foreign direct investment publication

Computing
 Field Device Integration, an International Electrotechnical Commission standards
 Flexible Display Interface
 Formatted Disk Image, part of the Unified emulator format

Health and medicine
 FDI World Dental Federation
 First dorsal interosseous, muscle in the hand

Politics
 Brothers of Italy (FdI, from the Italian name Fratelli d'Italia), an Italian political party
 Foundation for Democracy in Iran, a US-based Iranian dissident organization

Other uses
 Fault detection and isolation, in control engineering 
 Films Division of India, a government-owned company in India
 Frégate de défense et d'intervention, a class of frigates of the French Navy