diff --git a/src/map/Map.js b/src/map/Map.js
index a87b184b..e6d39674 100644
--- a/src/map/Map.js
+++ b/src/map/Map.js
@@ -286,7 +286,7 @@ L.Map = L.Class.extend({
 			zoom++;
 			nePoint = this.project(ne, zoom);
 			swPoint = this.project(sw, zoom);
-			boundsSize = new L.Point(nePoint.x - swPoint.x, swPoint.y - nePoint.y);
+			boundsSize = new L.Point(Math.abs(nePoint.x - swPoint.x), Math.abs(swPoint.y - nePoint.y));
 
 			if (!inside) {
 				zoomNotFound = boundsSize.x <= size.x && boundsSize.y <= size.y;