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Asked: 2026-05-28T05:17:20+00:00

Here are two hash generators: http://www.md5hashgenerator.com/index.php http://www.miraclesalad.com/webtools/md5.php Now, my question is: Why do the

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Here are two hash generators:

  1. http://www.md5hashgenerator.com/index.php
  2. http://www.miraclesalad.com/webtools/md5.php

Now, my question is:
Why do the hashes differ when trying to hash the char ‘€’ (0x80)?
I assume it happens because ‘€’ is not a normal ASCII character.
Which of the two hashes is ‘correct’?

I’m trying to calculate the hash returned by hash generator 1 with C#.
This hashing function doesn’t return it.

private string GetMD5Hash(string TextToHash)
{
        if ((TextToHash == null) || (TextToHash.Length == 0))
        {
            return string.Empty;
        }
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] textToHash = Encoding.Default.GetBytes(TextToHash);
        byte[] result = md5.ComputeHash(textToHash);
        return BitConverter.ToString(result).Replace("-", "").ToLower();
}

How could I change it so it returns the hash I want?

Additional Info:
I made a little AutoIt script:

#include  <Crypt.au3>
ConsoleWrite(StringLower(StringMid(_Crypt_HashData(Chr(128), $CALG_MD5),3)) & @CRLF)

and it returns the hash I want!
However I need a C# code 🙂

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1 Answer

  1. Editorial Team

    It comes down to which encoding you use to turn the string into a byte[] (hence my suggestion to use try UTF-8, as that is a pretty common choice here; however, any full unicode encoding would work as long as you know which to use) ; for example, based on the string "abc€" we can deduce that the first site might be using any of:

    874: Thai (Windows)
936: Chinese Simplified (GB2312)
1250: Central European (Windows)
1252: Western European (Windows)
1253: Greek (Windows)
1254: Turkish (Windows)
1255: Hebrew (Windows)
1256: Arabic (Windows)
1257: Baltic (Windows)
1258: Vietnamese (Windows)
50227: Chinese Simplified (ISO-2022)
51936: Chinese Simplified (EUC)
52936: Chinese Simplified (HZ)

    Personally, I’d use UTF-8!

    Here’s the code I used to find the candidate encodings:

        MD5 md5 = new MD5CryptoServiceProvider();
    foreach (var enc in Encoding.GetEncodings())
    {
        byte[] textToHash = enc.GetEncoding().GetBytes("abc€");
        byte[] result = md5.ComputeHash(textToHash);
        var output = BitConverter.ToString(result).Replace("-", "").ToLower();
        if(output == "7a66042043b2cc38ba16a13c596d740e")
        {  // result from http://www.md5hashgenerator.com/index.php
            Console.WriteLine(enc.CodePage + ": " + enc.DisplayName);
        }
    }

    Further, testing with the string "dnos ʇǝqɐɥdʃɐ" shows that the second site is definitely using UTF-8; the first site finds no matches, so I guess it is using a code-page based encoding, and in short will not work reliably with the full range of unicode.

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