<?php 

    $random = substr(md5(mt_rand()), 0, 7);

    echo $random;

?>

//generates 13 character random unique alphanumeric id

echo uniqid();

//output - 5e6d873a4f597

function rand_str() {

    $characters = '0123456789-=+{}[]:;@#~.?/>,<|\!"£$%^&*()abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';

    $randomstr = '';

    for ($i = 0; $i < random_int(50, 100); $i++) {

      $randomstr .= $characters[rand(0, strlen($characters) - 1)];

    }

    return $randomstr;

  }

function generateRandomString($digits) {

    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';

    $randstring = '';

    for ($i = 0; $i < $digits; $i++) {

        $randstring .= $characters[rand(0, strlen($characters))];

    }

    return $randstring;

}

echo generateRandomString(24);

    function RandomString()

    {

        $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';

        $randstring = '';

        for ($i = 0; $i < 10; $i++) {

            $randstring = $characters[rand(0, strlen($characters))];

        }

        return $randstring;

    }

$string = bin2hex(openssl_random_pseudo_bytes(10)); // 20 chars

$length = 10; // define the length of the random string

​

// define the characters to be used in the random string

$characters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';

​

$randomString = '';

for ($i = 0; $i < $length; $i++) {

    $randomString .= $characters[rand(0, strlen($characters) - 1)];

}

​

echo $randomString;

random_int ( int $min , int $max );