PHP Howto Read IP address of remote computer/browser

by nixCraft on February 27, 2006 · 22 comments· last updated at December 10, 2006

PHP has in built facility to detect remote browser or IP address and other properties. These values are assigned to special variable. In this case, it is assigned to variable called REMOTE_ADDR. You can use any one of the following statement to obtained or read IP address:

$ip = $_SERVER['REMOTE_ADDR'];
OR
$ip= $REMOTE_ADDR;

Here is sample code:

<? $ip= $REMOTE_ADDR; echo "<br> Your IP address : " . $ip; echo "<br> Your hostname : " . GetHostByName($ip); ?>

See PHP getenv for more information.

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{ 22 comments… read them below or add one }

1 soroccoheaven October 2, 2007 at 3:49 pm

hi,

I am trying to figure out the “spam” word enabled form submission like this one …anyone here can help me ..

Thanks

2 Dmitri Zhuchkov November 28, 2007 at 3:30 pm

echo “ Your hostname : ” . GetHostByName($ip);

You can get the host name from IP.gethostbyname

gethostbyname – Get the IP address corresponding to a given Internet host name

Try the gethostbyaddr for this task.

3 Rajesh January 2, 2008 at 1:23 pm

How to get the remote IP location?

4 Timmehx January 4, 2008 at 5:42 pm

<?php
$ip = $_SERVER['REMOTE_ADDR'];

And if you want to echo it use

that is what i use

5 Nilesh January 6, 2008 at 2:09 am

hey! this is a child’s play! such an easy thing! i said that coz i am 15 and a hard core PHP developer!!

6 Ben December 11, 2008 at 3:40 pm

I don’t understand something. 5 of my friends using different HOSTS in different CITIES used a script that logged each user’s IP address and time in a database and all their IP was exactly the same as mine. I used $_SERVER['REMOTE_ADDR']

7 Joshua April 22, 2011 at 10:12 pm: Hey ben, all of your IP’s are the same since all of you are using the same ISP or the same main ISP:
user1->ISP1->main_isp->internet
you->ISP3->main_isp->internet
So the website actually detects your main_isp IP address since none of you have a dedicated IP address on the internet.
Reply

8 Geert March 22, 2009 at 1:38 pm

They are all behind the same proxy-server. In that case $_SERVER['REMOTE_ADDR'] provides you with the ip-address of the proxy-server.

This function will determine the real ip-adress:

function ipCheck() {
		if (getenv('HTTP_CLIENT_IP')) {
			$ip = getenv('HTTP_CLIENT_IP');
		}
		elseif (getenv('HTTP_X_FORWARDED_FOR')) {
			$ip = getenv('HTTP_X_FORWARDED_FOR');
		}
		elseif (getenv('HTTP_X_FORWARDED')) {
			$ip = getenv('HTTP_X_FORWARDED');
		}
		elseif (getenv('HTTP_FORWARDED_FOR')) {
			$ip = getenv('HTTP_FORWARDED_FOR');
		}
		elseif (getenv('HTTP_FORWARDED')) {
			$ip = getenv('HTTP_FORWARDED');
		}
		else {
			$ip = $_SERVER['REMOTE_ADDR'];
		}
		return $ip;
	}

9 Sarmad Mahar June 17, 2010 at 4:47 am: it do not work if client computer is using ISA Server.
but code is working fine if client is connected with DSL , or modem direct internet connection.
can any one provide how do I resolved issue on intranet application/ Client is using ISA
Reply

10 leni June 10, 2009 at 5:47 pm

how can i get the ip address of the client requesting a particular url?
if possible give me a php code for the same..

11 Young Bobby October 22, 2009 at 3:21 pm

Yay;

Thanks it’s working fine !

12 chuman September 24, 2010 at 6:53 pm

supose am chatting with my friend using gtalk how would i get his ip address. [what command do i got to use in DOS]. what i got his ip what command [DOS} do i use to get his host name.
One more thing to what command to view that a specified computer is online or not.

13 DarkCoder November 29, 2010 at 3:10 pm

Seems not to work for ‘localhost’ but works well with other IPs in the system

14 Marko April 12, 2011 at 9:01 am

Why do you have 2 x same conditions in this script ?

elseif (getenv(‘HTTP_X_FORWARDED_FOR’)) {
$ip = getenv(‘HTTP_X_FORWARDED_FOR’); x 2
}
and

elseif (getenv(‘HTTP_FORWARDED’)) {
$ip = getenv(‘HTTP_FORWARDED’); x 2
}

15 Joshua April 22, 2011 at 10:49 pm: they arent 2 same conditions in the script marco, if you check back you will notice all the conditions have a slight difference
Reply

16 Magson Fernandes July 15, 2011 at 11:18 pm

Can any post a simple ip detection script or code. i need it please.

17 MoCua.Com August 6, 2011 at 8:46 pm

thanks and thanks

18 CodeSlayer September 1, 2011 at 12:18 am

Simple working excellent

<?php
$ip = $_SERVER['REMOTE_ADDR'];
$hostaddress = gethostbyaddr($ip);
$browser = $_SERVER['HTTP_USER_AGENT'];
$referred = $_SERVER['HTTP_REFERER']; // a quirky spelling mistake that stuck in php
print "Display IP address:";
print "$ip";
print "More detailed host address:";
print "$hostaddress";
print "Display browser info:";
print "$browser";
print "Where you came from (if you clicked on a link to get here:";
if ($referred == "") {
print "Page was directly requested";
}
else {
print "$referred";
}
?>

19 anand September 14, 2011 at 5:22 am