PowerShell Quick Tip 03 – What’s my external IP address? (Windows command-line)

At work this week I was working with one of our Linux engineers and he used the command “cURL ifconfig.me” which promptly provided him with the external IP of the system. I thought to myself, “I wonder if this is possible from PowerShell” and sure enough it is.

Using the Invoke-WebRequest cmdlet we can send http(s) requests to a web service. Note that this is a PowerShell 3.0 only cmdlet.

Let’s give it a try:

Invoke-WebRequest ifconfig.me

Not quite what we’re looking for. On inspection of the website http://ifconfig.me/ we can see that there are many command line options, lets try just the /IP option

Invoke-WebRequest ifconfig.me/ip

Much better and we can clearly see that the IP address is returned in Content which it fine for a quick check at the command line but not so great if your using it for scripting. To collect just the external IP we could wrap the command in parentheses, for example:

(Invoke-WebRequest ifconfig.me/ip).Content

Nice.

I thought that this would make a handy addition to my PowerShell Profile so I created a quick function

function Get-ExternalIP {
(Invoke-WebRequest ifconfig.me/ip).Content
}

Perfect!

An alternative to ifconfig.me is available at http://www.whatismyip.com/ip-faq/automation-rules/, for example

(Invoke-WebRequest http://automation.whatismyip.com/n09230945.asp).Content

Thanks for reading

Regards,

jfrmilner