PHP function to get visitor IP behind Cloudflare or proxy

Normally we’d use $_SERVER[‘REMOTE_ADDR’] but unfortunately this doesn’t work with Cloudflare. This small PHP function will let you get the visitor’s real IP address, even if your use Cloudflare or if they’re hiding behind a proxy.

$ip = getUserIP();

<?php
function getUserIP() {
	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;
}
?>