diff --git a/viewer/index.html b/viewer/index.html
index 6dbebc88c..687153790 100644
--- a/viewer/index.html
+++ b/viewer/index.html
@@ -11,7 +11,7 @@
         <meta name="author" content="cmv.io">
         <link rel="shortcut icon" href="./favicon.png">
         <title>Configurable Map Viewer</title>
-        <link rel="stylesheet" type="text/css" href="https://js.arcgis.com/3.20compact/esri/css/esri.css">
+        <link rel="stylesheet" type="text/css" href="https://js.arcgis.com/3.21compact/esri/css/esri.css">
         <link rel="stylesheet" type="text/css" href="css/theme/flat/flat.css">
         <link rel="stylesheet" type="text/css" href="css/cmv-theme-overrides.css">
         <link rel="stylesheet" type="text/css" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
@@ -50,7 +50,7 @@
         <!--[if lt IE 9]>
             <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/es5-shim/4.0.3/es5-shim.min.js"></script>
         <![endif]-->
-        <script src="https://js.arcgis.com/3.20compact/"></script>
+        <script src="https://js.arcgis.com/3.21compact/"></script>
         <script src="js/config/app.js"></script>
     </body>
 </html>