Depending where you are, you may have any number of IP addresses: one for your home network, one for your work network, and even one from the coffee shop providing free WiFi. Since it is not uncommon to have sites block you based on your IP address, it is good to be able to determine what yours is.
The site WhatIP.com does just that. It will tell you what country, ISP, and city it thinks you are in, along with your IP address.
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