Files with the extension .KDB are created using 'KeePass Password Safe'. Keepass is a free open source password manager that allows its users to store whole databases of passwords into one file, encrypt it, and lock and unlock it via one master password.

.KDB files encrypted using KeepPass utilise the Advanced Encryption Standard (AES, Rijndael) and the Twofish algorithms to encrypt its password databases. Both of which are considered to be very secure and are used by banks and other organisations to encrypt high-value information.

.KDB files contain the entire encrypted database created in KeePass, in addition to passwords, usernames and other notes, etc. are also encrypted within the .KDB file.