I have a list of 2,000 MD5 hashes that represent email addresses. I need someone to help me to reverse the MD5 strings back to the original email addresses.
Using hashlib library is the best solution for this question I think.
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hahaha you cannot reverse an md5 hash, best luck is to use a md5 reverse lookup using the rainbow tables, you could [this](https://crackstation.net/) to get the possible original, as md5 has collesions – Dean Van Greunen Aug 26 '23 at 16:06
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3the purpose of a hash is so it cannot be reversed – Dean Van Greunen Aug 26 '23 at 16:06
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1What's your reason for doing so? A hash function is not supposed to be reversible and breaking a hash is mostly used for nefarious purposes. – 5px Aug 26 '23 at 16:10
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@DeanVanGreunen I don't think that's true - the purpose of a standard hash is to reduce an arbitrary amount of data to a fixed size. _Cryptographic_ hash functions are of course a different matter. – snakecharmerb Aug 26 '23 at 16:42
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@snakecharmerb md5 is a Cryptographic hash – Dean Van Greunen Aug 27 '23 at 07:20
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@snakecharmerb md5 hash was used for Cryptographically storing passwords in hashed form – Dean Van Greunen Aug 27 '23 at 07:20
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You can't reverse a hash. You could crack it, as MD5 is prone to collisions, but the event of you getting the exact email is close to zero - you'll likely get an entirely different value whose MD5 hash matches yours but is not a valid email address.
If you're running a customer facing application and have no other ways of acquiring the addresses, you could check for a MD5 match against your database and if the user logs in then save the email.
5px
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1It's 128 bits. If we assume the email addresses use lower case ASCII letters, digits, '@' and '.', that's 5.15 bits per character. That allows 24.4 characters. And emails addresses are often shorter than that, so I think if you find a hash's shortest possible input string made from those characters, there's a decent chance that it's the correct email address. – Kelly Bundy Aug 26 '23 at 16:25