diff --git a/app/views/layouts/blank.html.erb b/app/views/layouts/blank.html.erb
index c7dcf2595..e51d98a91 100644
--- a/app/views/layouts/blank.html.erb
+++ b/app/views/layouts/blank.html.erb
@@ -2,6 +2,7 @@
 <html>
 <head>
   <title><%= yield :page_title %></title>
+  <meta name="viewport" content="width=device-width, initial-scale=1">
   <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
   <link rel="top" title="<%= Danbooru.config.app_name %>" href="/">
   <%= csrf_meta_tag %>
diff --git a/app/views/layouts/default.html.erb b/app/views/layouts/default.html.erb
index 2793d4c56..5bc4a5d48 100644
--- a/app/views/layouts/default.html.erb
+++ b/app/views/layouts/default.html.erb
@@ -2,6 +2,7 @@
 <html xmlns:fb="http://ogp.me/ns/fb#">
 <head>
   <title><%= yield :page_title %></title>
+  <meta name="viewport" content="width=device-width, initial-scale=1">
   <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
   <link rel="top" title="<%= Danbooru.config.app_name %>" href="/">
   <%= csrf_meta_tag %>
diff --git a/app/views/layouts/mobile.html.erb b/app/views/layouts/mobile.html.erb
index 09c50688e..f3296bfb7 100644
--- a/app/views/layouts/mobile.html.erb
+++ b/app/views/layouts/mobile.html.erb
@@ -2,6 +2,7 @@
 <html>
 <head>
   <title><%= yield :page_title %></title>
+  <meta name="viewport" content="width=device-width, initial-scale=1">
   <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
   <%= csrf_meta_tag %>
   <%= stylesheet_link_tag "mobile", :media => "screen" %>
