Detect the status of any webpage by sending an encoded URL as a query string. This returns a code as JSON.

status-detect.php

<?php
  header('Content-type: text/json');
  header('Content-type: application/json');

  $url = urldecode($_GET['url']);
  $ch = curl_init($url);
  curl_setopt($ch, CURLOPT_HEADER, true);
  curl_setopt($ch, CURLOPT_NOBODY, true);
  curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
  curl_setopt($ch, CURLOPT_TIMEOUT,10);
  $output = curl_exec($ch);
  $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
  curl_close($ch);

  $responseArray['status'] = $httpcode;
  echo json_encode($responseArray);
?>