diff --git a/_includes/head.html b/_includes/head.html
index 53f72c1..db2d185 100644
--- a/_includes/head.html
+++ b/_includes/head.html
@@ -156,7 +156,7 @@
         TeX: { equationNumbers: { autoNumber: "AMS" } }
         });
       </script>
-      <script type="text/javascript" async src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
+      <script type="text/javascript" async src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
     {% endif %}
 
 </head>