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PHP Extension

MX Lookup Mail Server Domain by Email Address

How to find the mail server for a given email address. Returns the domain name of the primary mail server.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$dns = new CkDns();
$json = new CkJsonObject();

$emailAddr = 'bob@example.com';

// This gets all MX domains for an email address.  (Typically one domain.)
// The preferred domain will be at index 0 (see below).
$success = $dns->Query('MX',$emailAddr,$json);
if ($success == false) {
    print $dns->lastErrorText() . "\n";
    exit;
}

$i = 0;
$count_i = $json->SizeOfArray('answer.mx');
while ($i < $count_i) {
    $json->put_I($i);
    $domain = $json->stringOf('answer.mx[i].domain');
    print $domain . "\n";
    $i = $i + 1;
}


?>