September 2, 2009
Back to Basics – Calculating MD5 Hashing
Yesterday I needed to
use a hashing algorithm
for a given task.
I chose to use the MD5
hashing algorithm and
in this post I’ll show how
to calculate MD5 hash from a given string.
What is MD5 Hashing Algorithm?
MD5 is a very widely used hashing function that commonly used to
check the integrity of files or strings. When using MD5 There is a
small possibility of getting two identical hashes to two different strings.
It is very useful for storing passwords in databases.
Calculating MD5 Hash from a String
MD5 hash function is provided in the BCL of .NET inside
The following code shows how to use the MD5 function to hash a given
public string CalculateMD5Hash(string input)
var md5Function = MD5.Create();
var inputBytes = Encoding.ASCII.GetBytes(input);
var hash = md5Function.ComputeHash(inputBytes);
var sb = new StringBuilder();
for (int i = 0; i < hash.Length; i++)
The code will creates MD5 hash algorithm class which is used to compute
the hash for the input string. After I’m computing the hash, I convert the
128 bit value to Hexadecimal upper case representation. If you want to use
lower case just replace the appending of the StringBuilder to the following
line of code:
After running this method on a given "Some String" string the result will be:
Computing hash using the MD5 hash algorithm class is very simple and straight
forward. In the post I showed how to do that using the BCL MD5 class.