WinMd5Sum (portable)

WinMd5Sum Portable is a simple MD5 sum checker that allows you to check and compare the md5 sums of files. 

What's an MD5 Sum? An MD5 sum is a cryptographic hash used to verify the integrity of files. So, when you download a file, you can check what the publisher says the MD5 sum is and compare it to the MD5 sum of the file you have.

http://portableapps.com/apps/utilities/winmd5sum_portable

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