PHP bin2hex() Function

The bin2hex() function in PHP converts a string to hexadecimal values. The conversion is done byte-wise with the high-nibble first.

Note: It is not for converting strings representing binary digits into hexadecimal.

Syntax:

bin2hex($string)

Parameters: This function accepts a single parameter $string. This is the string that will be converted to hexadecimal values.

Return Value: The function returns the hexadecimal value of the string passed in the parameter.

Examples:

Input : string = "geeks"
Output : 6765656b73

Input : string = "1111"
Output : 31313131 
Explanation: "1111" is converted to its hexadecimal 
values, it is not treated as a binary string, else the 
answer would have been F which is not in this case.

Below programs illustrate the bin2hex() function in PHP:

Program 1:

<?php
// PHP program to demonstrate
// the bin2hex() function

$str = "geeks";

echo bin2hex($str);

?>

Output:

6765656b73

Program 2:

<?php
// PHP program to demonstrate
// the bin2hex() function

$str = "1111";

echo bin2hex($str);

?>

Output:

31313131 

Reference:
http://php.net/manual/en/function.bin2hex.php