Is there a way to test if a string is an MD5 hash?

Question

I am trying to input a text file that contains MD5 hashes and keywords (one per line) into a C# app. Is there a way to check if a string is an MD5 hash? I looked on MSDN a

Answer 1

Well, an MD5 hash is really just binary data - if you've got a string then it's presumably encoded in some fashion, e.g. base64 or hex. You can test whether the string is correctly encoded for the right length of binary (16 bytes). That's all though - while there may be binary values which are never the result of hashing any data, I highly doubt that you can recognise such values. Ideally, there should be no such values, of course...