diff --git a/etc/koha-httpd.conf b/etc/koha-httpd.conf
index 3c68189f2f..71160a5b7a 100644
--- a/etc/koha-httpd.conf
+++ b/etc/koha-httpd.conf
@@ -200,7 +200,8 @@
 
      # Compress content with type html, text, and css, ...
      AddOutputFilterByType DEFLATE text/plain text/html text/xml text/css
-     AddOutputFilterByType DEFLATE application/xml application/xhtml+xml application/rss+xml application/javascript application/x-javascript
+     AddOutputFilterByType DEFLATE application/xml application/xhtml+xml application/rss+xml
+     AddOutputFilterByType DEFLATE application/javascript application/x-javascript application/json
 
      DeflateCompressionLevel 9