How do I find out what my external IP address is?

user_25201 0
Viewed 68054

My computers are sitting behind a router/firewall. How do I programmatically find out what my external IP address is. I can use http://www.whatsmyip.org/ for ad-hoc queries, but the TOS don't allow for automated checks.

Any ideas?

networking windows
13 Answers

http://ipecho.net/plain appears to be a workable alternative, as whatismyip.com now requires membership for their automated link. They very kindly appear to be offering this service for free, so please don't abuse it.

user_1030580

Unfortunately there is no easy way to do it.

I would use a site like www.whatsmyip.org and parse the output.

checkip.dyndns.com returns a very simple HTML file which looks like this:

<html>
  <head>
    <title>Current IP Check</title>
  </head>
  <body>
    Current IP Address: 84.151.156.163
  </body>
</html>

This should be very easy to parse. Moreover the site is exists for about ten years. There is hope that it will be around for a while.

user_846710

If you have access to a webserver with modphp, you can roll your own:

<?php print $_SERVER['REMOTE_ADDR']; ?>

If you don't want that to get abused, you'll have to keep it secret or add request limits.

I've been using one on my server for years.

Explicitly:

Create a file called whatismyip.php in your public_html folder in your website. It can be called anything and be anywhere in your webroot.

Add the line above, and then query your server:

curl http://example.com/whatismyip.php

for example.

guns_762880 
curl ifconfig.me

or

curl ifconfig.me/ip

Incase you don't have curl installed,

wget ifconfig.me/ip 2>/dev/null && cat ip

Hope this helps.

user_17757150

If the router you are behind speak UPnP you could always use a UPnP library for whatever language you are developing in to query the router for its external ip.

user_1300860

Another way is if you have access to a cloud email (yahoo, google, hotmail), send yourself an email. Then view the headers and you should see your IP address in there.

I would look up the exact area but the headers may vary from each implmentation, Look for the received-by and follow that until you get to something that looks like sent-by

EDIT: This answers the how to find IP address, not the via PROGRAMMATIC approach

Wayne_706830

whatismyip.com or ipchicken.com are very easy to parse.

If you have a webhost or vps you can also determine it, without fear of it randomly going down leaving you stuck.

user_81590
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