The .FDB extension refers to a generic Database file. These are mostly based on the Windows platform of Microsoft. These files are also referred to as Navision files.

While the file is very rare, it is still used widely in many financial applications and is used to store financial information on the Database software like Microsoft Dynamics NAV project. The program is mostly used for number crunching and business administration. The popularity of this format is its seemless connectivity with other frameworks because of the availability of JDBC drivers.