What is the program with the best encryption strength for a free program. I have some data that needs securing. I was thinking of a password protected algorithem that is a good algorithem and between 512 and 1024bit for the key.

what do you want to encrypt? files/folders/partitions/diskdrives/emails/etc?

I use TrueCrypt and KeePass for my encryption needs

http://www.truecrypt.org/

http://keepass.sourceforge.net/

just files/folders, although encrypting partitions does sound useful....

Anything based on RC4 or its variants can use variable key sizes, up to 2048 bits for RC4.

Blowfish - fast and secure if you have a 128-bit key.

thank you very much

Anything based on RC4 or its variants can use variable key sizes, up to 2048 bits for RC4.

RC4 has some weaknesses.

Blowfish - fast and secure if you have a 128-bit key.

128-bit: minimum.

Check 7-ZIP: Rijndael algorithm, 256-bit key, 256K hashes with SHA256.