diff --git a/examples/vector-esri.js b/examples/vector-esri.js
index 110c740412..823dea7877 100644
--- a/examples/vector-esri.js
+++ b/examples/vector-esri.js
@@ -13,7 +13,7 @@ goog.require('ol.style.Style');
 goog.require('ol.tilegrid');
 
 
-var serviceUrl = 'http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/' +
+var serviceUrl = 'https://sampleserver3.arcgisonline.com/ArcGIS/rest/services/' +
     'Petroleum/KSFields/FeatureServer/';
 var layer = '0';