Php how does md5 work

I hope you understood what is the definition of PHP md5 function with the syntax and its explanation, Info regarding the parameters in brief detail, Working of md5 function in PHP along with the various examples to understand the concept well. You can also go through our other related articles to learn more —.

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Show 2 more comments. Greg Hewgill Greg Hewgill k gold badges silver badges bronze badges. Thanks for the suggestion - it suprising how much you overlook the "low-tech" ways of doing this type of thing when they're probably the best methods.

And yes, I know about the md5 function ; — tom. Thanks Inshallah. M Rostami M Rostami 3, 1 1 gold badge 32 32 silver badges 37 37 bronze badges. This one works for me - the accepted answer produces a different value to the built in md5 function - cheers Mb — Graham. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.

Post as a guest Name. Email Required, but never shown. The Overflow Blog. Return Values Returns the hash as a character hexadecimal number. Actually, the warning should be in the operators section when comparing string values! By definition, zero raised to any power is zero. You can use to convert from raw md5-format to human-readable format. This function will concatenate all arguments, calculate the MD5 digest of this "message", and return it in binary form.

Thus, there is no way to actually "decrypt" an MD5 string. What you do is, you generate it from some data, then generate it from some other data, and compare the two MD5 strings. MD5 does not decrypt anything. It is considered a one-way hashing algorithm. For a given input it returns a fixed length string. Additionally, for two given inputs that are fairly similar but not identical the md5 value returned will not be predictable.

Hashing is good for a lot of things, for example file verification. Although off topic, if you took a file and computed a hash for it and then sent someone a file along with a hash they could easily verify they received the file correct by hashing it themselves and then asserting their hash matches the supplied hash. Another example would be something such as authentication on a site.

Md5 is not a good hash for this type of thing but hashing in general can help in situations such as these. MD5 is a cryptographic hash function. Cryptographic hash functions has the special property that they generate a result based on input, but it is almost impossible to recover the original input. It's kinda an "one-way encryption". Also, by passing the same data through a cryptographic hash function you should always get the same result.

While they are not preferred for encryption, since it's one-way only, but they are very useful when storing passwords. This is because, as I said, the same input would always have the same result. This makes storing the password in plain-text, or even recoverable version of it such as encrypted passwords unnecessary.

Instead, you would just generate a hash from the password and store it in a database.