Is SHA-256 Case Insensitive?

Question

I\'m running a service that is using SHA-256 on two sides of the application - one is a server-side PHP implementation and the other is a client-side iOS implementation. The

Answer 1

No decent cryptographic hash function is case insensitive, because then it would be far easier to produce a collision. The output is a different matter. It's basically a large number (so casing does not apply), but for convenience it is given in base 16, i.e. using the letters a through f as additional digits. Hexadecimal notation is indeed case insensitive, or at least both upper- and lowercase variants are common and recognized. It doesn't matter and does not change what number is represented.