diff --git a/app/views/layouts/default.html.erb b/app/views/layouts/default.html.erb
index 17401729b..271650eb7 100644
--- a/app/views/layouts/default.html.erb
+++ b/app/views/layouts/default.html.erb
@@ -5,6 +5,7 @@
   <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
   <link rel="top" title="<%= Danbooru.config.app_name %>" href="/">
   <%= csrf_meta_tag %>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
   <meta name="current-user-name" content="<%= CurrentUser.name %>">
   <meta name="current-user-id" content="<%= CurrentUser.id %>">
   <meta name="current-user-can-approve-posts" content="<%= CurrentUser.can_approve_posts? %>">