How to Get the Real Visitor IP Address Behind Proxies?

Getting Real Visitor IPs Behind Proxies

In cases where visitors use proxies, the standard PHP method $_SERVER['REMOTE_ADDR'] may not provide the actual visitor IP address. To address this issue, consider utilizing the following PHP code:

<code class="php">function getUserIP()
{
    // Handle CloudFlare network
    if (isset($_SERVER["HTTP_CF_CONNECTING_IP"])) {
        $_SERVER['REMOTE_ADDR'] = $_SERVER["HTTP_CF_CONNECTING_IP"];
        $_SERVER['HTTP_CLIENT_IP'] = $_SERVER["HTTP_CF_CONNECTING_IP"];
    }

    $client  = @$_SERVER['HTTP_CLIENT_IP'];
    $forward = @$_SERVER['HTTP_X_FORWARDED_FOR'];
    $remote  = $_SERVER['REMOTE_ADDR'];

    if(filter_var($client, FILTER_VALIDATE_IP))
    {
        $ip = $client;
    }
    elseif(filter_var($forward, FILTER_VALIDATE_IP))
    {
        $ip = $forward;
    }
    else
    {
        $ip = $remote;
    }

    return $ip;
}

$user_ip = getUserIP();

echo $user_ip; // Output real visitor IP address</code>

This code checks for CloudFlare networks and adjusts the IP address accordingly. It then examines HTTP_CLIENT_IP, HTTP_X_FORWARDED_FOR, and REMOTE_ADDR in that order, prioritizing IPs with valid formats. By implementing this code, you can obtain the real visitor IP address, even when they are behind a proxy.

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