PHP md5
(PHP 3, PHP 4, PHP 5)
PHP md5 -- Calculate the md5 hash of a string
PHP md5 Description
string md5 ( string str [, bool raw_output] )
Calculates the MD5 hash of str using the RSA Data Security, Inc. MD5 Message-Digest Algorithm , and returns that hash. The hash is a 32-character hexadecimal number. If the optional raw_output is set to TRUE , then the md5 digest is instead returned in raw binary format with a length of 16.
PHP md5 Definition and Usage
The PHP md5() function calculates the MD5 hash of a string.
The PHP md5() function uses the RSA Data Security, Inc. MD5 Message-Digest Algorithm.
From RFC 1321 - The MD5 Message-Digest Algorithm: "The MD5 message-digest algorithm takes as input a message of arbitrary length and produces as output a 128-bit "fingerprint" or "message digest" of the input. The MD5 algorithm is intended for digital signature applications, where a large file must be "compressed" in a secure manner before being encrypted with a private (secret) key under a public-key cryptosystem such as RSA."
This function returns the calculated MD5 hash on success, or FALSE on failure.
PHP MD5 Syntax
Parameter |
Description |
string |
Required. The string to be calculated |
raw |
Optional. Specifies hex or binary output format:
- TRUE - Raw 16 character binary format
- FALSE - Default. 32 character hex number
Note: This parameter was added in PHP 5.0 |
PHP MD5 Example 1
| <?php $str = "Hello"; echo md5($str); ?> |
The output of the code above will be:
| 8b1a9953c4611296a827abf8c47804d7 |
PHP MD5 Example 2
In this example we will print the result of md5() and then test it:
<?php $str = "Hello"; echo md5($str);
if (md5($str) == '8b1a9953c4611296a827abf8c47804d7')
{ echo "<br />Hello world!"; exit; } ?> |
The output of the code above will be:
| 8b1a9953c4611296a827abf8c47804d7 Hello world! |
| 
