diff --git a/sppa/calc/index.html b/sppa/calc/index.html
index d5bfaad0..f9c8d178 100644
--- a/sppa/calc/index.html
+++ b/sppa/calc/index.html
@@ -13,7 +13,7 @@
   </style>
 </head>
 <body>
-
+<center>
   <h2>calc</h2>
   <table>
     <tr>
@@ -62,6 +62,6 @@
       document.getElementById('display').value = '';
     }
   </script>
-
+</center>
 </body>
 </html>
