Use ipdata.co.
The API also provides geolocation data and has 10 global endpoints each able to handle >800M requests a day!
This answer uses a 'test' API Key that is very limited and only meant for testing a few calls. Signup for your own Free API Key and get up to 1500 requests daily for development.
$.get("https://api.ipdata.co?api-key=test", function (response) {_x000D_
$("#response").html(response.ip);_x000D_
}, "jsonp");
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<pre id="response"></pre>
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