is there a way to like unset the MD5?

[Jarod]

like if I inputted Jays, which is 3bc7b0fecbd8e586fcdaf70feaeaab9e in MD5, how do I reverse 3bc7b0fecbd8e586fcdaf70feaeaab9e so that it outputs Jays though?

[Alex]

MD5 cannot be reversed, that's the point.

[Jarod]

I guess, I was just curious though  :'(.

[joel24]

not exactly sure what you wanted it for, but you can encrypt/decrypt AES/DES encryptions with mysql...

http://dev.mysql.com/doc/refman/5.1/en/encryption-functions.html

[phpSensei]

Simple things like Jay or other strings that are md5 hashed can be reversed using brute force, which I won't go into details with. This is why having a combination of numbers and/or numbers with capitals and such can make it difficult for someone to decrypt passwords and such.

[RichardRotterdam]

I suggest looking up what the difference is between Hash and encryption. Also lookup what rainbow tables are and why people add "salt" to passwords. Looking those definitions up should inform you enough.

[Daniel0]

Hashing functions do not have an inverse because they're not bijections. It should be quite obvious why for instance MD5 isn't invertible. Its output is always 32-bit, so if you give it 33-bit input (or n-bit input for n > 32) you've lost information. How would you figure out what the last bit(s) should be?

 

Please not that you cannot "reverse" it by brute-force either. You can find input that has the same hash though. Kind of like n^2 = (-n)^2 but -n != n where n is a positive real number.