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&quot;In cryptography, MD5 (Message-Digest algorithm 5) is a widely used, partially insecure[1] cryptographic hash function with a 128-bit hash value. &quot;<br />
<a href="http://en.wikipedia.org/wiki/MD5" rel="ugc">http://en.wikipedia.org/wiki/MD5</a><br />
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If the md5 will return a 128bit hash value, why does the code return a 24 character string? And if the last 2 characters are always &quot;=&quot;, then isn't it useless?
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I think jpaulino deserves some points since he did answer my question, but ozo gets more credit for explaining why.
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Why is it that the last 2 bytes of the hash value are always &quot;=&quot;?<br />
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This is how I tested it:<br />
Dim MD5 As New System.Security.Cryptograp<wbr />hy.MD5Cryp<wbr />toServiceP<wbr />rovider<br />
Console.WriteLine(Convert.<wbr />ToBase64St<wbr />ring(MD5.C<wbr />omputeHash<wbr />(System.Te<wbr />xt.ASCIIEn<wbr />coding.ASC<wbr />II.GetByte<wbr />s(&quot;test&quot;))<wbr />))<br />
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Am I doing something wrong?<br />

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Why is it that the last 2 bytes of the hash value are always "="?

This is how I tested it:
Dim MD5 As New System.Security.Cryptography.MD5CryptoServiceProvider
Console.WriteLine(Convert.ToBase64String(MD5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes("test"))))

Am I doing something wrong?


MD5 Hash

The .NET Framework is not specific to any one programming language; rather, it includes a library of functions that allows developers to rapidly build applications. Several supported languages include C#, VB.NET, C++ or ASP.NET.

.NET Programming

Visual Basic .NET (VB.NET) is an object-oriented programming language implemented on the .NET framework, but also supported on other platforms such as Mono and Silverlight. Microsoft launched VB.NET as the successor to the Visual Basic language. Though it is similar in syntax to  Visual Basic pre-2002, it is not the same technology,

Visual Basic.NET

Encryption is the process of encoding messages or information in such a way that only authorized parties can read it. In an encryption scheme, the intended communication information or message, referred to as plaintext, is encrypted using an encryption algorithm, generating ciphertext that can only be read if decrypted. For technical reasons, an encryption scheme usually uses a pseudo-random encryption key generated by an algorithm. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients, but not to unauthorized interceptors.