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<?php $str = "aHR0cHM6Ly93d3cnVuY3Rpb24uc3RyLXNwbGl0LnBocA=="; $devide = 3; $char = '*'; // that not used in your string $add = $devide - strlen($str)%$devide; $total = strlen($str) + $add; $str = str_pad($str,$total,$char,STR_PAD_LEFT); $result = str_split($str, $total/$devide ); var_dump($result);

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