A simple snippet to get co-ordinates of array of address's.

get_geo_co-ordinate.js

/*    Get the latitude and longitude from address:
      Author        : Bastin Robins J
      Modified By   : Gaurav Mehla
*/

//     Add the link to webpage
<script src="https://maps.googleapis.com/maps/api/js?key=API_KEY_HERE" type="text/javascript"></script>

<script>
(async function(){
  // List of addressed you want to get co-ordinates of
  let address = [
      'New York',
      'Nariman Point, Mumbai, India'
  ]

  //Function to covert address to Latitude and Longitude
    var getLocation =  function(address) {
      return new Promise(function(resolve, reject){
          var geocoder = new google.maps.Geocoder();
          geocoder.geocode( { 'address': address}, function(results, status) {
            if (status == google.maps.GeocoderStatus.OK) {
                  var latitude = results[0].geometry.location.lat();
                  var longitude = results[0].geometry.location.lng();
                  setTimeout(() => {
                    resolve({latitude, longitude});
                  }, 500);  // 500ms wait for API Quota Limit
                } 
          });
      }); 
    }

  for (let index = 0; index < address.length; index++) {
    //Call the function with address as parameter
    let res = await getLocation(address[index]);
    console.log(index + 1, JSON.stringify(res));

  }

})();
</script>