diff --git a/app/templates/consume.html b/app/templates/consume.html
index ae2325a..d9e553a 100644
--- a/app/templates/consume.html
+++ b/app/templates/consume.html
@@ -18,7 +18,7 @@
 							<div class="center">
 								<h2>{{product.name}}</h2>
 								{% set fils = "product_%s.png" % product.name %}
-								<img src="{{ url_for('static', filename=fils) }}" /><br>
+								<img src="{{ url_for('static', filename=fils) }}?{{timestamp}}" /><br>
 							</div>
 							<div class="right">
 							{{"%0.2f" % product.price}} €
diff --git a/app/templates/fridges.html b/app/templates/fridges.html
index 22d88d3..2ef6aa0 100644
--- a/app/templates/fridges.html
+++ b/app/templates/fridges.html
@@ -15,7 +15,7 @@
                 <div class="fridge_sensor">
                     {{ sensor.name }}<br>
                     {% set fils = "log_%s.png" % sensor.id %}
-                    <img src="{{ url_for('static', filename=fils) }}" /><br>
+                    <img src="{{ url_for('static', filename=fils) }}?{{timestamp}}" /><br>
                 </div>
                 {% endfor %}
             </div>
diff --git a/app/templates/index.html b/app/templates/index.html
index 24d88d3..de6ce27 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -2,7 +2,7 @@
 {% set title = "Bierliste" %}
 {% block content %}
 	<h1> Bierliste </h1>
-	<img src="{{ url_for('static', filename='bierliste_small.png') }}" style="width:100%;max-width:990px;">
+	<img src="{{ url_for('static', filename='bierliste_small.png') }}?{{timestamp}}" style="width:100%;max-width:990px;">
 	<!-- <table>
   		<tr>
     		<th>ID</th>
diff --git a/app/templates/personal.html b/app/templates/personal.html
index 6121214..a122fde 100644
--- a/app/templates/personal.html
+++ b/app/templates/personal.html
@@ -4,10 +4,10 @@
 	<h1> Statistik </h1>
 	<div>
 	<h2> Bierkonsum </h2>
-	<img src="{{ url_for('static', filename='total.png') }}">
+	<img src="{{ url_for('static', filename='total.png') }}?{{timestamp}}">
 	{% if user %}
         {% set fils = "total%03d.png" % user.id %}
-    	<img src="{{ url_for('static', filename=fils) }}">
+    	<img src="{{ url_for('static', filename=fils) }}?{{timestamp}}">
 	{% endif %}
 	</div>
 	<h1> Abrechnung </h1>
diff --git a/app/views.py b/app/views.py
index 428d397..7b74f97 100644
--- a/app/views.py
+++ b/app/views.py
@@ -13,7 +13,12 @@ from consumption import Consumption
 import bcrypt
 import os
 from settings import *
+import time
 
+# makes the variable timehex available in all templates
+@app.context_processor
+def inject_time():
+    return dict(timestamp=time.time().__int__())
 
 @app.route('/static/<path:path>')
 def static_proxy(path):