As of PHP 5.1.2 can use hash() to convert data to SHA-256 hash value. hash() is part of the php core. Can hash with various algorithms. This will create a 256 bit hash value which requires a 64 length character field to store it. Each hex character requires 4 bits to store. $hash = hash(‘sha256′, [...]

md5 or sha1 creates 128 bit hash value of the original value. The original value cannot be obtained from a hash value. This is the best way to store a representation of passwords. These older hashing algorithms have weakness though. The SHA-2 family of hashing algorithms is latest and most secure methods to hash data. [...]