Generating a random hex color code with PHP

Get a random number from 0 to 255, then convert it to hex:

function random_color_part() {
    return str_pad( dechex( mt_rand( 0, 255 ) ), 2, '0', STR_PAD_LEFT);
}

function random_color() {
    return random_color_part() . random_color_part() . random_color_part();
}

echo random_color();

you can use md5 for that purpose,very short
$color = substr(md5(rand()), 0, 6);

$rand = dechex(rand(0x000000, 0xFFFFFF));
echo('#' . $rand);