diff --git a/include/ui.js b/include/ui.js
index e029358f..62c561af 100644
--- a/include/ui.js
+++ b/include/ui.js
@@ -48,7 +48,7 @@ load: function() {
     UI.initSetting('host', '');
     UI.initSetting('port', '');
     UI.initSetting('password', '');
-    UI.initSetting('encrypt', false);
+    UI.initSetting('encrypt', (window.location.protocol === "https:"));
     UI.initSetting('true_color', true);
     UI.initSetting('cursor', false);
     UI.initSetting('shared', true);
diff --git a/vnc_auto.html b/vnc_auto.html
index 2ac5e030..77df8bb0 100644
--- a/vnc_auto.html
+++ b/vnc_auto.html
@@ -101,7 +101,8 @@
             }
 
             rfb = new RFB({'target':       $D('noVNC_canvas'),
-                           'encrypt':      WebUtil.getQueryVar('encrypt', false),
+                           'encrypt':      WebUtil.getQueryVar('encrypt',
+                                    (window.location.protocol === "https:")),
                            'true_color':   WebUtil.getQueryVar('true_color', true),
                            'local_cursor': WebUtil.getQueryVar('cursor', true),
                            'shared':       WebUtil.getQueryVar('shared', true),