diff --git a/app/views/layouts/_footer.html.haml b/app/views/layouts/_footer.html.haml
index c2a34b496..76377dd89 100644
--- a/app/views/layouts/_footer.html.haml
+++ b/app/views/layouts/_footer.html.haml
@@ -7,5 +7,5 @@
     .col-md-4#footer3
       != cms_snippet_content(:footer3)
       %div{ style: "float: right;" }
-        %a{ href: "http://opendefinition.org/ossd/" }
-          %img{ src: "http://assets.okfn.org/images/ok_buttons/os_80x15_blue.png", alt: "" }
+        %a{ href: "https://opendefinition.org/ossd/" }
+          %img{ src: "https://assets.okfn.org/images/ok_buttons/os_80x15_blue.png", alt: "" }