Tresor is a file and folder encryption application for Macintosh. It combines high cryptographic security and ease of use. Integrated compression functions allow compression and encryption in a single pass, without any interim files. Filter functions allow you to automate complex encryption tasks without the use of risky scripts. Being developed outside the US, Tresor is available in all countries that allow cryptography.

Tresor encrypts the complete content of any file using IDEA™ block encryption. It takes a passphrase of arbitrary length and produces a 160-bit hash value using the Secure Hash Algorithm (SHA). It then takes 128 bits of this hash value, using them as the encryption key for IDEA™. For decryption the same passphrase will be needed again.

IDEA™ (International Data Encryption Algorithm) is a block encryption algorithm that uses data blocks of 64 bits and a key length of 128 bits. IDEA™ was developed at the Institute for Signal and Information Processing of the Swiss Federal Institute of Technology, Zurich, by James L. Massey and Xuejia Lai and is regarded as the most secure block encryption algorithm publicly available today. IDEA™ is patented. Any use of the algorithm for commercial purposes requires a licence from MediaCrypt Ltd. By buying a license for Tresor, you automatically acquire the right to use the IDEA™ algorithm with Tresor.

Although you may freely download Tresor from our web site and try it out, Tresor is not freeware. If you decide to use Tresor, you have to licence your copy. A licence costs € 25.-- per copy (VLA possible from 4 copies up).