Sometimes you may need to know your public IPv4 address. If you have an open browser window you may go to https://www.whatismyip.com/ or to http://canihazip.com/. However, I prefer the latter for two reasons:

  1. It has a cleaner and simpler interface: it just shows your IP address.
  2. Has a script friendly version: http://canihazip.com/s which just prints your IP in text/plain.

So to get your public IP address from a shell:

$ IP=$(curl -s http://canihazip.com/s)

or 

$ IP=$(wget -qO - http://canihazip.com/s)

Unfortunately, neither of the above mentioned sites work for IPv6 addresses.

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