Return Center polygon in google maps v3. This does not apply to some shapes though. I recommend using turf.js instead https://turfjs.org/

polygonCenter.js

function polygonCenter(poly) {
    var lowx,
        highx,
        lowy,
        highy,
        lats = [],
        lngs = [],
        vertices = poly.getPath();

    for(var i=0; i<vertices.length; i++) {
      lngs.push(vertices.getAt(i).lng());
      lats.push(vertices.getAt(i).lat());
    }

    lats.sort();
    lngs.sort();
    lowx = lats[0];
    highx = lats[vertices.length - 1];
    lowy = lngs[0];
    highy = lngs[vertices.length - 1];
    center_x = lowx + ((highx-lowx) / 2);
    center_y = lowy + ((highy - lowy) / 2);
    return (new google.maps.LatLng(center_x, center_y));
  }

Yes, for this to work, just modify the var declarations at the top to read :

var lowx, highx, lowy, highy, lats = [], lngs = [], center_x, center_y, vertices = poly.getPath();

Excellent job, it works beautifully. Thanks.

Doesn't work when the polygon is a triangle:

http://jsfiddle.net/fn3nbvuy/290/?utm_source=website&utm_medium=embed&utm_campaign=fn3nbvuy

great it! Thanks.

Hi guys, This was written a while ago just to solve a simple problem. I am surprised this is being used.
Though you might want to use turf.js instead for your map related operations. It can be easily used with Google maps or any JS map libraries. 😄 🗺️

A great solution or https://arxiv.org/ftp/arxiv/papers/1212/1212.3193.pdf

it works fine! thanks!

That's great. You can also check this function turf.centerOfMass or centroid
https://turfjs.org/docs/#centerOfMass