diff --git a/calibration.html b/calibration.html
index c6d465d..0a932de 100644
--- a/calibration.html
+++ b/calibration.html
@@ -35,7 +35,7 @@
         <p>Watch the videos and then work through each tab. I have created a custom gcode generator to assist in making testing towers. This used to be a laborious process and beyond the skills of many users. Other times pre-sliced gcode was used from the internet, but it is impossible to have gcode available for every printer configuration. <i>Until now!</i></p>
         <div class="warning">
             <h2>Warning - Read carefully!</h2>
-            <p>Every attempt has been made to ensure this is safe but ultimately there always is risk in running pre-sliced gcode from the internet. Preview the gcode in your slicer or <a href="http://gcode.ws/" target="_blank">Gcode.ws</a> and <span style="color:red; font-weight: bolder;">print at your own risk.</span></p>
+            <p>Every attempt has been made to ensure this is safe but ultimately there always is risk in running pre-sliced gcode from the internet. Preview the gcode in your slicer or <a href="http://zupfe.velor.ca" target="_blank">Zupfe GCode Viewer</a> and <span style="color:red; font-weight: bolder;">print at your own risk.</span></p>
             <p>Only print this gcode when you are present, alert and capable of stopping the printer in case of emergency.</p>
             <p>Validation has been built into the forms to only allow sensible min and max values, however this is not foolproof.</p>
         </div>
diff --git a/js/createform.js b/js/createform.js
index 3db7e43..c79742e 100644
--- a/js/createform.js
+++ b/js/createform.js
@@ -455,7 +455,7 @@ var endGcode = /*html*/ `<h4>Additional end gcode</h4>
     <textarea name="endgcode"></textarea>
 </div>`;
 
-var preview = /*html*/ `<p>It is advised to preview the generated gcode through your slicer or <a href="http://gcode.ws/" target="_blank">Gcode.ws</a> before printing.`;
+var preview = /*html*/ `<p>It is advised to preview the generated gcode through your slicer or <a href="http://zupfe.velor.ca" target="_blank">Zupfe GCode Viewer</a> before printing.`;
 
 function createForm(n){
     document.write('<input type="hidden" name="description" value="'+n+'">')