PassCryptor keeps your passwords safe with strong encryption using the Twofish Cypher. You don't have to remember all your passwords anymore with this easy to use management tool. Includes one-click link and copy password to clipboard features. Free 30 day trial version. Twofish is a block cipher by Counterpane Labs. It was one of the five Advanced Encryption Standard (AES) finalists. Twofish is unpatented, and the source code is uncopyrighted and license-free.