Q:

How can I get the smallest LatLngBounds that still contains a set of Lat/Long Coordinates in Google Maps JS API?

I need to plot a set of coordinates on the map in response to a user selection, and when it happens, I'd like to pan the map to focus on that set of points. How can I find the smallest bounding box (LatLngBounds) that contains all of the coordinates?

A:

In addition to the Stack Overflow post which @Crescent Fresh pointed to above (which is using the v2 API), the method you'd want to use is the LatLngBounds.extend().
Here's a complete example, using the v3 API:
<!DOCTYPE html>
<html> 
<head> 
   <meta http-equiv="content-type" content="text/html; charset=UTF-8"/> 
   <title>Google Maps LatLngBounds.extend() Demo</title> 
   <script src="http://maps.google.com/maps/api/js?sensor=false" 
           type="text/javascript"></script> 
</head> 
<body> 
   <div id="map" style="width: 400px; height: 300px;"></div> 

   <script type="text/javascript"> 

   var map = new google.maps.Map(document.getElementById('map'), { 
     mapTypeId: google.maps.MapTypeId.TERRAIN
   });

   var markerBounds = new google.maps.LatLngBounds();

   var randomPoint, i;

   for (i = 0; i < 10; i++) {
     // Generate 10 random points within North East America
     randomPoint = new google.maps.LatLng( 39.00 + (Math.random() - 0.5) * 20, 
                                          -77.00 + (Math.random() - 0.5) * 20);

     // Draw a marker for each random point
     new google.maps.Marker({
       position: randomPoint, 
       map: map
     });

     // Extend markerBounds with each random point.
     markerBounds.extend(randomPoint);
   }

   // At the end markerBounds will be the smallest bounding box to contain
   // our 10 random points

   // Finally we can call the Map.fitBounds() method to set the map to fit
   // our markerBounds
   map.fitBounds(markerBounds);

   </script> 
</body> 
</html>

Screenshot:

