diff --git a/kfet/context_processors.py b/kfet/context_processors.py
index 6c053ea9..9364c724 100644
--- a/kfet/context_processors.py
+++ b/kfet/context_processors.py
@@ -22,6 +22,6 @@ def kfet_open(request):
     kfet_force_close = KFET_FORCE_CLOSE()
     return {
             'kfet_open': kfet_open,
-            'kfet_open_date': kfet_open_date,
+            'kfet_open_date': kfet_open_date.isoformat(),
             'kfet_force_close': kfet_force_close,
         }
diff --git a/kfet/static/kfet/js/kfet_open.js b/kfet/static/kfet/js/kfet_open.js
index e2cccf81..a8f41757 100644
--- a/kfet/static/kfet/js/kfet_open.js
+++ b/kfet/static/kfet/js/kfet_open.js
@@ -56,18 +56,8 @@ function kfet_open(init_date, init_status, init_force_close, force_close_url, fo
         });
     }
 
-    function nb_min_diff() {
-        var date_now = new Date();
-        // On calcule le nb de minutes depuis le dernier
-        // envoi d'information
-        tmp = date_now - kfet_open_date;
-
-        tmp = Math.floor(tmp/1000);             // Nombre de secondes entre les 2 dates
-        diff_sec = tmp % 60;                    // Extraction du nombre de secondes
-
-        tmp = Math.floor((tmp-diff_sec)/60);    // Nombre de minutes (partie entière)
-        
-        return tmp;
+    function kfet_open_min() {
+        return moment().diff(kfet_open_date, 'minute')
     }
     function do_kfet_close() {
         kfet_open_bullet.css({'background-color': closed_color});
@@ -85,7 +75,7 @@ function kfet_open(init_date, init_status, init_force_close, force_close_url, fo
         open_status.html("?????");
     }
     function update_open() {
-        var nb_min = nb_min_diff();
+        var nb_min = kfet_open_min();
         console.log("K-Fêt ouverte : " + (kfet_open&&(!force_close)));
         console.log(nb_min + " minute(s) depuis la dernière mise à jour");
         if (force_close) {
@@ -121,7 +111,7 @@ function kfet_open(init_date, init_status, init_force_close, force_close_url, fo
         if (data['door_action']) {
             console.log("* Message reçu de la part de la porte.");
 
-            kfet_open_date = new Date(data['door_action']['kfet_open_date']);
+            kfet_open_date = moment.utc(data['door_action']['kfet_open_date']);
             kfet_open = data['door_action']['kfet_open'];
 
             update_open();
diff --git a/kfet/templates/kfet/base.html b/kfet/templates/kfet/base.html
index 81ca3dfd..d992b209 100644
--- a/kfet/templates/kfet/base.html
+++ b/kfet/templates/kfet/base.html
@@ -21,13 +21,17 @@
     <script type="text/javascript" src="{% static 'kfet/js/kfet_open.js' %}"></script>
     <script type="text/javascript" src="{% static 'kfet/js/reconnecting-websocket.js' %}"></script>
 
+    <script type="text/javascript" src="{% static 'kfet/js/moment.js' %}"></script>
+    <script type="text/javascript" src="{% static 'kfet/js/moment-fr.js' %}"></script>
+    <script type="text/javascript" src="{% static 'kfet/js/moment-timezone-with-data-2010-2020.js' %}"></script>
+
     {# K-Fêt open #}
     <script type="text/javascript">
     $(document).ready(function () {
         $('#genericteam').on('click', function () {
             setTimeout(function () { location.reload() }, 1000);
         });
-        init_date = new Date("{{ kfet_open_date.isoformat }}");
+        init_date = moment.utc("{{ kfet_open_date }}");
         init_status = {{ kfet_open | yesno:"true,false"}};
         init_force_close = {{ kfet_force_close | yesno:"true,false"}};
         force_close_url = "{% url 'kfet.force_close' %}?close";
diff --git a/kfet/templates/kfet/kpsul.html b/kfet/templates/kfet/kpsul.html
index e401a910..313c9a46 100644
--- a/kfet/templates/kfet/kpsul.html
+++ b/kfet/templates/kfet/kpsul.html
@@ -8,9 +8,6 @@
 <script type="text/javascript" src="{% static 'kfet/js/js.cookie.js' %}"></script>
 <script type="text/javascript" src="{% static 'kfet/js/jquery-ui.min.js' %}"></script>
 <script type="text/javascript" src="{% static 'kfet/js/jquery-confirm.js' %}"></script>
-<script type="text/javascript" src="{% static 'kfet/js/moment.js' %}"></script>
-<script type="text/javascript" src="{% static 'kfet/js/moment-fr.js' %}"></script>
-<script type="text/javascript" src="{% static 'kfet/js/moment-timezone-with-data-2010-2020.js' %}"></script>
 <script type="text/javascript" src="{% static 'kfet/js/history.js' %}"></script>
 {% endblock %}
 
diff --git a/kfet/views.py b/kfet/views.py
index 7865ec34..0a3b6f99 100644
--- a/kfet/views.py
+++ b/kfet/views.py
@@ -97,7 +97,7 @@ class UpdateKfetOpen(View):
         websocket_data = {
                 'door_action': {
                     'kfet_open': is_open,
-                    'kfet_open_date': timezone.now(),
+                    'kfet_open_date': timezone.now().isoformat(),
                     },
                 }
         consumers.KfetOpen.group_send('kfet.is_open', websocket_data)