PHP : Get client IP address

Knowing who is accessing your web server can be useful for tracking a user's activity. In this tutorial, we will learn how to get client IP address with PHP.

In a straight forward manner, this should be get your the IP address of a client

 $_SERVER['REMOTE_ADDR']

However, sometimes the user access your web server via a proxy or load balancer ( such as in cloud hosting, behind a LAN, etc ) and the above code will give you the IP address of the proxy or load balancer.

You need to get the HTTP Request header information "X-Forwarded-For (XFF)" in order to get the real IP address of the client. To do that you can use

 $_SERVER['HTTP_X_FORWARDED_FOR']

and

 $_SERVER['HTTP_CLIENT_IP']

The PHP code snippet below should do the job :

 if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
 $client_ip = $_SERVER['HTTP_CLIENT_IP'];
 } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
 $client_ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
 } else {
 $client_ip = $_SERVER['REMOTE_ADDR'];
 }

Hope this simple tutorial can be useful to you.