intl-tel-input/examples/gen/js/defaultCountryIp.js

A JavaScript plugin for entering and validating international telephone numbers

var input = document.querySelector("#phone");
window.intlTelInput(input, {
  initialCountry: "auto",
  geoIpLookup: function(callback) {
    $.get('https://ipinfo.io', function() {}, "jsonp").always(function(resp) {
      var countryCode = (resp && resp.country) ? resp.country : "";
      callback(countryCode);
    });
  },
  utilsScript: "../../build/js/utils.js?1541153396801" // just for formatting/placeholders etc
});