WordPress Config: Use X-Forwarded-For HTTP Header to Get Visitor's Real IP Address

wp-config.php

// Use X-Forwarded-For HTTP Header to Get Visitor's Real IP Address
	
if ( isset( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
	$http_x_headers = explode( ',', $_SERVER['HTTP_X_FORWARDED_FOR'] );

	$_SERVER['REMOTE_ADDR'] = $http_x_headers[0];
}

Thanks for this tip. It's exactly what I was looking for, Ryan.
Any chance this option will become available as a plugin, so regular Wordpress users don't have to touch the code?
@luisan00, mira esto :)

Thanks

Works perfectly with Cloudflare! Thank you

Thanks. Working with Ithemes Security plugin behind proxy.

For anyone hosting their WordPress blog on Heroku: the left-most IP is not guaranteed to be the client's real IP, while the right-most one should be, as per this answer .