Online PHP editor | output for pBKf2

<?php class Base64Url { /** * @param $str string * * @return string */ public static function encode($str) { $std = @base64_encode($str); if ($std === false) { throw new \Exception('base64_encode() failed'); } return rtrim(strtr($std, '+/', '-_'), '='); } /** * @param $str string * * @return string */ public static function decode($str) { $result = ''; if ($str !== null) { if (!is_string($str)) { throw new \Exception('Only strings can be decoded'); } $std = strtr($str, '-_', '+/').str_repeat('=', strlen($str) % 4); $result = base64_decode($std, true); if ($result === false) { throw new \Exception('base64_decode() failed'); } } return $result; } } $ph = '{"typ":"JWT",' . "\n ". '"alg":"HS256"}'; echo Base64Url::decode(Base64Url::encode($ph));