diff --git a/default.html5 b/default.html5
index 365ad0681..14bff6286 100644
--- a/default.html5
+++ b/default.html5
@@ -3,6 +3,7 @@
 <head>
   <meta charset="utf-8">
   <meta name="generator" content="pandoc">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
 $for(author-meta)$
   <meta name="author" content="$author-meta$">
 $endfor$
