MD5 Function

Hi, I am trying to verify the return size that MD5 function returns. I dont see
any details mentioned about this in the docs.

Basically i am planning on storing passwords as md5(password) and want to know
if i can just declare the password field to be something like VARCHAR(32) or
even CHAR(32) if it's guaranteed that it will never be longer/shorter than 32
chars.

Perhaps this is not that big of a deal and i could as easily just declare it as
VARCHAR/TEXT without the size constraint. I just want to know what is best
storage and performance wise?

Thanks,

Aaron