diff --git a/lib/middleware/anonymous_cache.rb b/lib/middleware/anonymous_cache.rb
index f80507ee510..5eeb6030fa8 100644
--- a/lib/middleware/anonymous_cache.rb
+++ b/lib/middleware/anonymous_cache.rb
@@ -44,8 +44,13 @@ module Middleware
         @is_crawler == :true
       end
 
+      def accept_html?
+        accept = @env["HTTP_ACCEPT"]
+        !!(accept && accept =~ /html/)
+      end
+
       def cache_key
-        @cache_key ||= "ANON_CACHE_#{@env["HTTP_HOST"]}#{@env["REQUEST_URI"]}|m=#{is_mobile?}|c=#{is_crawler?}"
+        @cache_key ||= "ANON_CACHE_#{accept_html?}_#{@env["HTTP_HOST"]}#{@env["REQUEST_URI"]}|m=#{is_mobile?}|c=#{is_crawler?}"
       end
 
       def cache_key_body